Family Owned & Operated Since 1971• Bakersfield, CA
pH meters, conductivity meters, dissolved oxygen, ORP, and turbidity instruments
72 product families(115 total products)
Recall Min, Max and Average readings. Featuring Data Hold and a Built-in RS-232 PC serial interface with optional data acquisition software and data logger. Auto power off saves battery life. DO measurements from 0 to 20.0 mg/L. Complete with 0.8" (20mm) diameter probe on 13ft (4m) cable, 5 membranes, rubber holster, 9V battery and hard case.
The DO210 is a Dissolved Oxygen Meter which measures DO from 0 to 20.0mg/L, Oxygen Percent from 0 to 100.0% and Temperature with ATC. This meter features Adjustable Altitude and Salinity Compensation as well as min, max and data hold functions. Complete with DO probe with membrane and 39" (1m) cable, two spare replacement membranes, electrolyte, 9V battery and soft case.
The ExStik II DO600 meter displays Oxygen level as percent of Saturation from 0 to 200. 0 percent or Concentration from 0 to 20.00 ppm (mg/L). It features Adjustable Altitude Compensation (0 to 20,000 feet in 1,000 ft. increments), Adjustable Salinity Compensation from 0 to 50 ppt and an analog bargraph for indicating trends. DO600 meter includes a DO electrode, protective sensor cap, spare membrane cap, electrolyte, four 3V CR-2032 batteries, and 48" (1.2m) neck strap.
The Extech DO603 is a replacement screw-on membrane kit for the Dissolved Oxygen sensor (DO605) of a DO600 meter.
Replacement dissolved oxygen sensor for ExStik DO meter
The 9-in-1 DO700 Kit measures DO concentration/saturation, pH, mV, Temperature, Conductivity, TDS, Salinity, and Resistivity. It features automatic salinity compensation and manual barometric pressure compensation for DO measurements. In addition, it has automatic one button calibration of 4, 7 and 10 pH with a choice of three-point calibration for better accuracy and it provides automatic temperature compensation. Complete with DO probe, pH/mV/Temp electrode, polymer Conductivity cell, pH and Conductivity calibration solutions, batteries and hard carrying case.
The Extech SDL150 records data on an SD card in Excel format. It has a dual backlit display of oxygen concentration and temperature. It measures dissolved oxygen from 0 mg/L to 20.0 mg/L and 0% to 100.0% oxygen, plus temperature from 0°C to 50°C (32 to 122°F). Includes automatic temperature compensation from 0°C to 50°C via temperature probe sensor built into polarographic type oxygen probe. Offset adjustment used for zero function to make relative measurements. The SDL150 stores 99 readings manually and 20M readings via a 2G SD card. User programmable sampling rate. It has a built-in PC interface, min/max and data hold functions, and an auto power off. Complete with 6 x AA batteries, SD card, probe, two spare replacement membranes, electrolyte, and hard carrying case.
Measure DO between 0.0 and 199.9%. Color coded for easy identification and installation. Lasts more than 1 year with typical usage and regular maintenance.
CL200 is an ExStik Chlorine Meter. This revolutionary technique measures Direct Total Residual Chlorine from 0.01ppm to 10ppm. It makes non-subjective measurements unaffected by interferences associated with traditional colorimeters and spectrophotometers like sample color, turbidity, light, and pollutants. This product comes with an electrode, five packs of 10 reagent tablets (50 tests), a protective sensor cap, a sample cup with cap, four CR2032 batteries, and a 48” neck strap.
The CL205 is an Extech ExStik Replacement Chlorine Electrode Module. Product for use with Extech CL200 Meter. The CL205 is an electrode capable of measuring chlorine and temperature. Comes with a 6 month warranty.
The CL207 is a Chlorine Calibration Standard for CL200 ExStik Waterproof Chlorine Meter. Product comes with 3 ampules.
Specifically designed for the quick and accurate measurement of fluoride ions in drinking water and other aqueous samples, the ExStik FL700 incorporates a sensing electrode, measuring electronics, and display in one convenient package, making this unit ideal for field or laboratory testing. The FL700 is capable of direct reading of total fluoride from 9.99 ppm or mg/L down to 0.1ppm, and the meter provides automatic temperature compensation (±10 degrees C of calibration temperature). Complete with electrode, TISAB reagent tablets, sensor cap, four 3V button batteries, and 48" (1.2m) neckstrap.
The Extech FL704 is a set of 100 TISAB Fluoride Reagent Tablets. No messy powder reagents and no dosing equipment required.
TB400 is a Portable Turbidity Meter that tests water, food, beverages and other aqueous solutions. Meter comes complete with all the accessories to conveniently test the turbidity of municipal water, food and beverage water, and other aqueous solutions where fluid clarity is important. Portable design allows you to take measurement on-site instead of bringing solution back to the lab. Measures up to 1000 NTU (Nephelometric Turbidity Unit) with 0.01 NTU resolution. Complete with 0 NTU standard solution test bottle, 100 NTU standard solution test bottle, cleaning solution (distilled water), (2) test bottles and covers, cleaning cloth, six AAA batteries, and hard carrying case.
Conductivity Standard 2 Bottles -- 1 Pint Each
Conductivity Standard 2 Bottles -- 1 Pint Each
The Extech EC150 is a Conductivity/TDS/Temperature Meter with high-accuracy multi-ranging sensor. It features auto power off with disable, adjustable conductivity to TDS ratio factor from 0.4 to 1.0, data hold and low battery indication. The waterproof design withstands wet environment and meets IP65 standard. Includes meter, protective sensor cap, and four LR44 button batteries.
The EC170 is a Salinity Meter with Waterproof design (IP65). Measure salinity in aquaculture, environmental studies, ground water, koi ponds, irrigation, drinking water and other applications. Features a High accuracy multi-ranging sensor and Auto Power off with disable. Autoranging with 2 ranges of measurement. Data Hold, Auto Power Off and Low Battery Indication. Complete with salinity sensor, protective sensor cap, and 4 LR44 button batteries.
The Extech EC210 is a compact, handheld Conductivity Meter. Its long-life, carbon rod combination electrode measures conductivity, TDS and temperature. The meter features three ranges for conductivity and TDS, plus adjustable temperature compensation factor to maintain accuracy. Units of measure include µS/cm, mS/cm, ppm, °F, and °C.
The Extech EC400 ExStik features six units of measure, internal memory that stores up to 15 labeled readings for easy recall, adjustable conductivity to TDS ratio factor from 0.4 to 1.0, and self-calibration upon power up. The EC400 incorporates the latest microprocessor chip technology and patented sensor technology to enable the simultaneous measurement of conductivity, TDS, salinity, and temperature. With the touch of a button the EC400 allows you the flexibility of interchangeable cell constants and has made the job of testing fast, accurate, and repeatable. Complete with meter and Conductivity cell, protective cap, sample cup, four CR2032 batteries, and 48"(1.2m) neckstrap.
The Extech EC405 is an ExStik Replacement Conductivity Cell Module. For use with the EC400 Conductivity/TDS/Salinity Meter. It is an easy to clean, rugged conductivity cell module. Product comes with a protective connector cap and a one year warranty.
The EC500 is Conductivity/TDS/Temperature Meter. Measures 5 parameters including Conductivity, TDS, Salinity, pH, and Temperature using one electrode. Analog bargraph indicates trends. Memory stores up to 25 labeled readings. Waterproof meter with high-accuracy multi-ranging sensor. Features Auto Power off with disable. Complete with meter and electrode, protective cap, sample cup, four 3V CR-2032 batteries, and 48" (1.2m) neckstrap.
The EC505 is an ExStik Replacement pH Electrode/Conductivity Cell Module. For use with the Extech EC500 Waterproof ExStik II pH/Conductivity Meter. Measures conductivity, TDS, salinity, pH and temperature. Comes with a year warranty.
The EC510 is a conductivity testing kit. Kit includes EC500 meter, 3 calibration standards, 3 pH buffer pouches plus rinse solution, 3 cups, batteries and carrying case. Measures 5 parameters including conductivity, TDS, salinity, pH and temperature using one electrode. Analog bargraph indicates trends. Memory stores up to 25 labeled readings. Adjustable Conductivity to TDS ratio from 0.4 to 1.0; 0.5 fixed Salinity ratio.
The 7-in-1 EC600 Kit measures Conductivity, TDS, Salinity, Resistivity, pH, mV and Temperature. It has automatic one button calibration of 4, 7 and 10 pH with a choice of three point calibration for better accuracy and it provides automatic temperature compensation. One point conductivity calibration automatically recognizes eight calibration solutions from USA, Europe, and China. Memory stores up to 300 readings with series number, measured value and temperature. The meter has a large, blue, backlit LCD display screen with an auto power off function with disable that saves battery life. The IP57 waterproof housing protects it from the elements. Complete with pH/mV/Temperature electrode, polymer Conductivity cell, pH and Conductivity calibration solutions, batteries and hard carrying case.
Cell for EC600/DO700. The Extech EC605 is a replacement or spare Conductivity Cell for use with the EC600 portable water conductivity meter and DO700 portable dissolved oxygen meter. Product comes with a six-month warranty.
The Extech EC700 water quality tester kit is your all-in-one solution. With interchangeable probes, it measures pH, conductivity, TDS, salinity, and dissolved oxygen—making it perfect for aquaculture, laboratories, water treatment plants, and more. Its rugged IP67 waterproof design, large LCD display, and auto temperature compensation ensure reliable results wherever you go.
The Extech RF20 measures the concentration of dissolved salt in fluids. It has a compact size and is easy to operate. Automatic Temperature Compensation (ATC) from 10°C to 30°C. Comes with case, calibration screwdriver, plastic pipette calibration solution, and user guide.
Replacement Conductivity Probe with Protective Cap for EC700
The Extech EX900 ExStik 4-In-1 Kit includes a CL200 meter, pH and ORP electrodes, reagent tablets (50 tests), four plastic cups, a weighted stand, pH buffer pouches, four CR2032 batteries, 48-inch neck strap, carrying case, and user manual. The meter measures total chlorine, pH, ORP, and temperature with interchangeable flat surface electrodes that are included. Flat surface electrodes work in liquids, semi-solids and solids. Built-in memory can store/recall up to 15 readings and save the last calibrated value. It has a large 3-1/2 digit (2000 count) digital display with a bargraph and an automatic electronic self-calibration function for chlorine and ORP (1, 2, or 3 point buffer calibration for pH).
Buffer Solution/ pH 10 2 One Pint Bottles
The waterproof ExStik PH100 pH meter by Extech is a rugged, accurate, reusable stick pH meter with unique data storage features that make it exceptionally easy to use. The flat surface electrode allows you to measure pH in liquids, semi-solids, and solids while limiting electrode breakage and clogged junctions. The LCD readout displays pH, temperature, and an analog bar graph that shows trends in acidity or alkalinity and indicates when the reading is stable. Other features include automatic temperature compensation, auto power off, low battery indicator and data hold. The PH100 comes with a protective sensor cap, sample cup, four 3V CR2032 button batteries and a 48 in. (1.2 m) neck strap. For more convenience, purchase the EX006 weighted base, which holds both the sample cup and ExStik meter.
Extech PH103 are convenient, pre-measured pH calibration solutions for your meter. Included is a rinsing solution used for cleaning off the pH electrode before and after taking measurements to prevent contamination (6 pouches of pH4 solution, 6 pouches of pH7 solution, 6 pouches of pH10 solution, 2 pouches of rinse solution).
The Extech PH105 pH ExStik Electrode Module is an easy to clean, rugged flat surface pH electrode. It is interchangeable with the ExStik Chlorine or ORP meters and measures in liquids, semi solids and solids. Also, it has the ATC via the built-in PT-100 Ohm sensor. The Extech PH105 pH ExStik Electrode Module comes complete with the protective connector cap.
Now you can test pH on the spot easily and accurately with the ExStik PH110 Waterproof pH Meter. The durable ExStik meter features a flat surface refillable electrode for measuring pH in liquids, semi-solids, and solids – no more electrode breakage or clogged junctions. Since you can refill the ExStik quickly, you won't need to worry about the shelf life of its electrode. the ExStik meter is an invaluable tool for measuring the pH in shampoo, body wash, facial cleansers, lotions, creams, and more. Use it to monitor pools and spas, or to measure acidity and alkalinity in soil, skin, and carpeting. It's valuable in hydroponic gardening or farming. Get important readings in cement, agriculture, fish farming, wastewater, antifreeze recycling, food preparation, cleaning supplies, and manufacturing of paper, pulp, and paint. Comes complete with the refillable pH electrode, a 1.5mL bottle KCI, two reference junctions, two removal tools, a protective cap, a sample cup, four 3V CR-2032 batteries, and a 48 inch (1.2m) neck strap.
Replacement flat surface electrode for ExStik
pH Meter, Palm pH with Cabled Electrode
The Extech PH300 pH/Temperature Kit measures pH, mV, and temperature at your workbench or in the field. It has automatic, one button calibration of 4, 7 and 10 pH with a choice of three point calibration, for better accuracy and automatic temperature compensation. Memory stores up to 200 readings with series number, measured value, and temperature. The meter has a large, blue, backlit LCD display screen with an auto power off function plus disable function that saves battery life. The IP57 waterproof housing protects it from moisture and the elements. Comes with a pH/mV/temp electrode, a protective rubber holster, the pH calibration solutions (4, 7, and 10 pH), two AA batteries, hard carrying case, and user manual.
The Extech PH305 is an electrode capable of measuring pH, mV and temperature. For use with the PH300 Waterproof pH/mV/Temperature Kit, EC600 Waterproof Conductivity Kit, and DO700 Portable Dissolved Oxygen Meter. Comes with a 6 month warranty.
Buffer Solution/ PH4 2 One Pint Bottles
Buffer Solution/PH7, Two One Pint Bottles
Rugged waterproof (IP57) housing with Flat Surface Electrode for measuring pH in liquids, semi-solids, and solids. Does not break or get junctions clogged like the traditional glass bulb electrodes. Easy to replace sensor is perfect for field or lab use.
ORP meter with rugged flat surface ORP electrode and high resolution of 1mV
The Extech RE305 ORP ExStik Electrode Module is an easy to clean, rugged, flat surface ORP electrode that is interchangeable with ExStik chlorine or pH meters. It measures in liquids, semi solids and solids. The RE305 comes complete with the protective connector cap.
Records data on an SD card in Excel format
Replacement pH probe with protective cap for Extech EC700, 6-in-1 water quality meter. Measure pH between 2.00 and 12.00. Color coded for easy identification and installation. Lasts more than 6 months with typical usage and regular maintenance.
Multi-parameter four-wire liquid analysis transmitter — modular electronics support a wide range of measurement combinations including differential conductivity, dual oxygen, pH/ORP + chlorine, and many more. Drives most industrial, commercial, and municipal liquid-analysis applications from a single transmitter platform. Backlit graphical display with multi-language UI. The mid-tier Rosemount Analytical transmitter — broader sensor support than the 56, less channel count than the 1057.
Triple-channel liquid analysis transmitter — three independent pH/ORP and/or conductivity inputs in one transmitter housing. Reduces installed cost and panel space when a process requires multiple measurements at a single location (boiler-feedwater plants, electrochemistry plants, multi-tank monitoring). Modular sensor-input cards. Same UI family as the 1056. Best when consolidating three sensors that would otherwise need separate single-channel transmitters.
Single-channel liquid analysis transmitter — drives one sensor (pH/ORP, contacting or toroidal conductivity, dissolved oxygen, chlorine, ozone, turbidity). Same modular electronics platform as the 1056 / 1057. The single-channel choice for tight panel-space installations where a 1056 dual is over-spec, but a loop-powered 5081 isn't suitable (need full 4-wire operation, broader I/O, larger display).
Single-channel loop-powered (4-20 mA HART) liquid analysis transmitter in an explosion-proof housing. Accepts pH/ORP, contacting / toroidal conductivity, and amperometric (DO / chlorine / ozone) sensors. Rugged weatherproof corrosion-resistant enclosure for hazardous-area installations (Class I Div 1, Zone 1) — the Rosemount Analytical choice when other transmitters need separate explosion-proof enclosures and conduit fittings. Loop-powered means no separate power supply or 4-wire conduit run.
Dual-channel liquid analysis transmitter — accepts two independent sensor inputs (any combination of pH/ORP, contacting / toroidal conductivity, resistivity, dissolved oxygen, free chlorine, total chlorine, ozone, turbidity). Large color graphical display with intuitive menu structure. Used in water/wastewater plants, chemical process plants, and any installation where two analytical measurements share one transmitter location for cost efficiency.
Toroidal conductivity sensor with robust, fouling-resistant geometry for harsh, corrosive, and fibrous liquid applications — pulp & paper, sugar processing, food/beverage CIP/SIP. Same 0-2 S/cm range as the 228 but with body materials and dimensions optimized for process applications with extreme fouling potential. The 226 outlasts the 228 in fibrous and abrasive media; the 228 wins in tighter pipes (smaller form factor).
Toroidal (inductive) conductivity sensor that reliably measures conductivity in highly conductive electrolyte solutions up to 2 S/cm (2,000,000 µS/cm). The toroidal design — no metal electrodes touching the process — makes it the right choice for dirty and corrosive applications where contacting sensors (like the 400) foul or corrode. Best for chlor-alkali, salt brines, acid/caustic transfer, and waste streams. Mounting variants for in-pipe insertion, flow-through, and submersion.
Contacting (electrode) conductivity sensor for clean, low-conductivity liquids — high-purity water, ultrapure rinse water, clean cooling water, condensate. Factory-measured cell constant (0.01, 0.1, or 1.0/cm) ensures out-of-the-box accuracy with no initial calibration. Wetted parts: titanium electrodes, 316 SST body, PEEK insulator, EPDM O-rings. Direct screw-in 3/4 in MNPT process insertion. Range: <20,000 µS/cm. The right choice when sample is clean — toroidal sensors (228 / 226) are over-spec for ultrapure water.
Premium pH/ORP sensor for high-temperature, high-pressure, fouling/coating applications — robust design significantly prolongs sensor life in complex chemistries (chlor-alkali, semiconductor, hydrocarbon). Resists fouling, coating, and reference-junction poisoning that defeat standard pH sensors. VP variable-pin connector option (3300HTVP) for VP-cable compatibility with the 1056 / 1057 / 5081 transmitters. The Rosemount Analytical workhorse for severe-service pH measurement.
Mid-tier general-purpose pH/ORP sensor with double-junction reference — protects the reference element from poisoning ions (ammonia, chlorine, cyanides, sulfides) that kill single-junction reference sensors. Wide range of installation styles: insertion, submersion, retractable. Cost-effective workhorse for water/wastewater, general process, and any application where the 3300HT premium would be over-spec. VP version (3900VP) for variable-pin connector compatibility.
pH/ORP sensor designed for harsh, dirty, abrasive applications — lime slurry waste treatment, paper-machine headbox, pigment/dye production, and any process with large quantities of suspended solids. Wear-resistant body and reference geometry that survives where standard 3900 sensors fail in months. Insertion mounting standard. VP connector option (396PVP). The Rosemount choice for the dirtiest pH measurement jobs.
Membrane-covered amperometric dissolved oxygen sensor — continuously measures DO between 0-20 ppm. The lower-cost alternative to the optical RDO when daily calibration burden is acceptable and maintenance staff is regularly on-site. Best for municipal and industrial wastewater aeration basins, where the 499ADO has decades of installed-base reliability. Membrane and electrolyte are field-replaceable; rebuild kits available for multi-year sensor life.
Optical (luminescent-quenching) dissolved oxygen sensor — measures DO in wastewater aeration basins, ponds, and surface water without the membrane fouling, electrolyte depletion, or zero-drift issues of older membrane DO sensors. No daily zero calibration. Typical sensor life 1-2 years between cap replacements (vs 3-6 months for membrane). Best for municipal wastewater aeration optimization, fish farming, and any DO measurement where maintenance burden has historically been a problem. The Rosemount choice when 499ADO membrane sensor's lower cost is outweighed by maintenance time.
Mid-tier acoustic leak detector with backlit analog meter and a bank of 6 selectable band-pass filters (100/200/400 Hz low-side, 600/800/1200 Hz high-side) plus a Filter-Thru mode for 15 Hz–30 kHz full-spectrum listening. 62 dB amp, 110 dB hearing-protection limiter, 28 hr on 6× AA. Tunable analog filtering without digital complexity.
High-sensitivity acoustic leak detector built around a neodymium-magnet sensor (10 V/g) with dual-range filtering — high 30 Hz–5000 Hz for surveying, low 30 Hz–800 Hz for pinpointing, plus a 150–180 Hz notch. IP68 submersible sensor with 9.75 ft cable, 80-hour runtime on 4× C cells. SSI's pick when raw sensitivity and audio quality are the priorities.
Top-of-line pinpoint leak detector with automatic DSP noise reduction that filters out intermittent interference (passing vehicles, conversations, footsteps) no analog model can reject. Onboard memory stores up to 250 sound recordings with min-noise-level detection across multiple pipe locations. 10 selectable filters (5 high / 3 low / 2 notch for 50 & 60 Hz hum), IP67 piezo sensor. The right pick for noisy urban environments or when you need to document your findings.
Pinpoint acoustic leak detector with digital display, 900 V/G sensitivity, and eight selectable high-pass / low-pass bandpass combinations (100 Hz–5000 Hz range). Includes Android smart-phone app for location logging. Direct successor to the LD-16 on SSI's 2026 lineup.
Compact all-purpose acoustic leak detector — one handheld amplifier with three interchangeable attachments (three-point ground plate, magnetic base, contact rod) handles both survey sweeps and pinpointing. 100 Hz–1500 Hz, 56 dB amp, 2× AA cells for ~30 hr runtime, 8 lb total kit. The do-everything entry pick.
Rod-based survey listening instrument purpose-built for walking water distribution systems at hydrants, meters, and valves. Built-in A/C hum notch filter (transformers / power lines), 55 dB amplifier, 100 Hz–2000 Hz response, 3-range sensitivity, stereo leather-cup headphones. Ships with a short 4" rod and a 4-section 13" threaded rod set.
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