16,000+ results for orp
- Milwaukee Instruments pH and ORP Meter bundle (MW102 PRO+ & MW500 PRO)Opens in a new window or tabBrand New$289.30Top Rated Plusgetultimatenow (3,207) 100%Free shippingFree returns
- EMERSON ROSEMOUNT ORP SENSOR 3900VP-02-12Opens in a new window or tabNew – Open box$399.95Top Rated Pluscncsalvage11 (4,445) 100%+$15.10 shippingFree returns
- EMERSON ROSEMOUNT ORP SENSOR 396PVP-12-55Opens in a new window or tabNew – Open box$1,399.95Top Rated Pluscncsalvage11 (4,445) 100%+$15.10 shippingFree returns
- 7 in 1 Digital LCD PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Tester Meter PenOpens in a new window or tab❤️900+Sold✔️IP67 Waterproof✨60Day Free Return⭐Save15%UPBrand New8 product ratings - 7 in 1 Digital LCD PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Tester Meter Pen$21.48Save up to 15% when you buy moreList price: $30.98 31% offTop Rated Plusredtagtown (360,894) 99.3%Free shippingFree returns1,160 sold
- 7 in 1 Digital LCD PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Tester Meter PenOpens in a new window or tabBrand New$20.48Save up to 10% when you buy moreList price: $33.98 40% offTop Rated Pluspartsdomauction (333,351) 99.4%Free shippingFree returns3,139 sold
- 7 in 1 Digital LCD PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Tester Meter PenOpens in a new window or tabBrand New$21.48Save up to 10% when you buy moreList price: $30.98 31% offTop Rated Plusnsioutlet (526,388) 99.3%Free shippingFree returns377 sold
- Apera Instruments GroStar Series GS1-P pH/ORP Pen Tester Kit With Double JunctioOpens in a new window or tabBrand New$66.50Save up to 15% when you buy morexac_co (493) 100%Free shipping3 watchers
- 10 in1 Digital LCD PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Tester Meter PenOpens in a new window or tabBrand New$28.98Save up to 10% when you buy moreList price: $42.98 33% offTop Rated Plusredtagtown (360,894) 99.3%Free shippingFree returns100 sold
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Sponsored | Top selling items from highly rated sellers with free shipping- Neptune Systems PM1 pH/ORP Probe ModuleOpens in a new window or tabPre-Owned$10.00supsup-3 (2) 100%1 bid · Time left5d 18h left (Thu, 10:14 AM)+$5.93 shipping
- 10 in 1 Digital Backlight PH/TDS/EC/ORP/TEMP/SG/Salt Water Quality Tester MeterOpens in a new window or tabBrand New$28.98Save up to 10% when you buy moreList price: $42.98 33% offTop Rated Plusthesiliconvalley (460,660) 99.5%Free shippingFree returns233 sold
- Neptune Systems Apex Lab Grade ORP Probe NEW NEVER USEDOpens in a new window or tabBrand New$60.00mrowe82604 (145) 100%Free shipping
- ORP Tester Meter -1999mV~1999mV Millivolts Pool Aquarium Redox Digital PenOpens in a new window or tabBrand New$14.00Save up to 15% when you buy moresvyatoslavbogatyrev (173) 96.7%Free shipping
- Digital LCD PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Tester Meter Pen KitsOpens in a new window or tabBrand New$6.68 to $22.45Save up to 10% when you buy morebig-sales-store2017 (9,454) 97.8%Free shippingFree returns
- Milwaukee MW500 PRO ORP Meter with Hard Carrying CaseOpens in a new window or tabBrand New$167.00Top Rated Plusgetultimatenow (3,207) 100%Free shippingFree returns
- ORP Pen Tester Electrode-extended up to 80 mm:Range+-1999 mV+-2%FS Carrying CaseOpens in a new window or tabBrand New$53.50hitech-gngroup (2,791) 100%+$16.90 shippingLast one3 watchers
- Portable Digital Water Quality Meter Tester LCD PH/TDS/EC/ORP/TEMP/SG/SalinityOpens in a new window or tabBrand New$6.68 to $22.45sysports2020 (5,147) 97.7%Free shippingFree returns
- New ListingMyron PT3 - MYRON L Ultrapen - ORPOpens in a new window or tabPre-Owned$75.00sassykoi (1,504) 100%+$5.93 shipping
- Apera Instruments 3M KCL Storage Soaking Solution (8 oz.) for pH and ORP...Opens in a new window or tabBrand New$19.71shahafh12012 (37) 100%Free shippingFree returnsLast one
- ORP/pH/Temperature Tester (HI98121) - Hanna InstrumentsOpens in a new window or tabBrand New$196.00Save up to 6% when you buy moresaltwateraq (55,310) 99%Free shipping38 sold
- Milwaukee MA9016 Cleaning Solution for pH / ORP ElectrodesOpens in a new window or tabBrand New$19.99Save up to 10% when you buy moreTop Rated PlusFree shippinggetultimatenow (3,207) 100%Free returns
- 8 in 1 Digital PH/TDS/EC/ORP/TEMP/S.G/Salinity/H2 Water Quality Tester Meter PenOpens in a new window or tabBrand New$23.98Save up to 10% when you buy moreTop Rated PlusFree shippingnsioutlet (526,388) 99.3%Free returns
- HM Digital ORP-200 Waterproof ORP MeterOpens in a new window or tabBrand New$89.99Top Rated Plusgetultimatenow (3,207) 100%Free shippingFree returnsLast one7 sold
- 10 in 1 Digital LCD PH/TDS/EC/ORP/TEMP/SG/Salt/H2 Water Quality Tester Meter PenOpens in a new window or tabBrand New$28.98Save up to 10% when you buy moreList price: $42.98 33% offTop Rated Plusnsioutlet (526,388) 99.3%Free shippingFree returns119 sold
- Water Quality Tester Meter Pen 7 in 1 Digital LCD PH/TDS/EC/ORP/TEMP/SG/SalinityOpens in a new window or tabBrand New$20.89Top Rated PlusWas: $27.85 25% offeverydaygadgetz (236,862) 99.1%Free shippingFree returns64 sold
- 10 in1 Digital LCD PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Tester Meter PenOpens in a new window or tabBrand New$28.98Save up to 10% when you buy moreList price: $42.98 33% offTop Rated Pluspartsdomauction (333,351) 99.4%Free shippingFree returns2,106 sold
- Milwaukee PH-MAIN Maintenance Kit for pH / ORP Meters and TestersOpens in a new window or tabBrand New$29.99Top Rated Plusgetultimatenow (3,207) 100%Free shippingFree returns
- 10 in1 Digital LCD PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Tester Meter PenOpens in a new window or tabBrand New$28.98Save up to 10% when you buy moreList price: $42.98 33% offTop Rated Pluseeekitonline (451,991) 99.1%Free shippingFree returns
- 7 in 1 Water Quality Tester Digital LCD Meter Pen PH/TDS/EC/ORP/TEMP/SG/SalinityOpens in a new window or tabBrand New$21.85Top Rated Plusshoppingg_joy (49,664) 98.1%Free shippingFree returns
- New ListingDigital LCD PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Tester Meter Pen KitsOpens in a new window or tabBrand New$17.00Save up to 18% when you buy moreararak67 (0) 0%Free shipping
- Biopharm pH/ORP Electrode Storage Solution 8 oz (250 mL)Opens in a new window or tabBrand New$14.50biopharminc (2,136) 100%Free shipping429 sold
- Intelligent Wireless Water Quality Monitor, PH/ORP/Salt, Solar Residual ChlorineOpens in a new window or tabBrand New$92.6266soar66 (601) 96.4%Was: $99.59 7% offFree shippingfrom China
- Cole-Parmer 500 PH 500 pH/ORP/Temperature 1/4 DIN ControllerOpens in a new window or tabPre-Owned$282.12Top Rated PlusWas: $313.47 10% offilovestuff2019 (1,138) 100%Free shippingFree returns
- 7 in 1 Water Tester Digital Salinity Tester PH Meter/TDS /EC Meter ORP for WaterOpens in a new window or tabBrand New$23.38tmarketq (3,078) 98.7%Free shippingFree returns
- Milwaukee MA9011 Refilling Electrolyte Solution 3.5M KCl for pH/ORP electrodesOpens in a new window or tabBrand New$26.99Top Rated Plusgetultimatenow (3,207) 100%Free shippingFree returns
- Milwaukee pH600-BOX LED Pocket pH Tester with Calibration SolutionOpens in a new window or tabBrand New$31.95anatek_electronics (1,360) 100%Free shippingFree returns
- Milwaukee MA9020 ORP Meter Check Solution, 200-275 mV, 230mlOpens in a new window or tabBrand New$14.94eseasongear (52,324) 99.4%+$6.70 shipping92 sold
- 7 in1 Digital LCD PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Tester Meter PenOpens in a new window or tabBrand New$20.99goalgoab (873) 95.8%Free shippingfrom China
- 7 In 1 Backlight PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Meter Tester!!Opens in a new window or tabBrand New$29.61superplaza-07 (941) 100%Free shippingFree returns
- Smart Monitor Fish Tank WIFI SPA Pool Water Quality Meter PH ORP EC PPM TesterOpens in a new window or tabBrand New$77.68 to $78.29llucky666 (790) 98.4%Was: $89.29 13% off+$9.99 shippingfrom China
- Rosemount 3900-02-10 General Purpose pH/ORP SensorOpens in a new window or tabBrand New$1,200.00bonnie2884 (148) 100%+$12.41 shipping
- PH‑803W PH ORP Controller Alkalinity Controller Water Quality Monitor Tool USOpens in a new window or tabBrand New$138.13$7 off every $100 with couponWas: $146.95 6% offnicedeal_123 (2,163) 99.3%Free shippingFree returns
- Digital LCD PH/TDS/EC/ORP/TEMP/Salinity Water Quality Tester Meter Pen DetectorOpens in a new window or tabBrand New$18.99 to $24.69Save up to 10% when you buy moreWas: $19.99 5% offsunnylives (54,313) 97.3%Free shipping
- 7 In 1 Backlight PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Meter Tester L3Opens in a new window or tabBrand New$29.99Top Rated Plusleteasyauto-03 (155) 100%Free shippingFree returns
- 7 in 1 Digital LCD PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Tester Meter PenOpens in a new window or tabBrand New$20.99aumillet2 (182) 96.4%Free shippingfrom China
- 2in1 / 4in1 Portable Tem H2 Orp Ph Meter Dissolved Hydrogen Water Quality TesterOpens in a new window or tabBrand New$17.66 to $18.56modulefans (115,404) 99.1%Was: $18.99 7% off+$3.00 shippingfrom China
- 4 In 1 Portable Water Quality Meter Tester Hydrogen-Rich Test Pen PH/ORP/H2/TEMPOpens in a new window or tabBrand New$22.68hjw_bike4 (60) 98.4%Free shippingfrom ChinaAlmost gone11 sold
- 8 In 1 Multi Parameter Water Quality Tester S.G PH EC SALT ORP TDS CF TEMP 230VOpens in a new window or tabBrand New$95.14Extra 8% off with couponWas: $101.21 6% offyundet22 (182) 97.9%Free shippingFree returns
- Waterproof-pH-ORP-C-Combo-Tester-Meter with Automatic CalibrationOpens in a new window or tabBrand New$155.95anatek_electronics (1,360) 100%Free shippingFree returns
- 8 in 1 Digital PH EC Meter LCD Tester Pocket Hydroponics Aquarium Water Test PenOpens in a new window or tabBrand New$21.48ark_auto_parts (1,868) 99.3%Free shippingFree returns
- Vollara living Water Portable 4 In 1 Hydrogen-Rich Test Pen PH/ORP/TEMP WaterOpens in a new window or tabBrand New$39.50thewaterlight (3,973) 100%Free shipping
- Portable 4 In 1 Hydrogen-Rich Test Pen PH/ORP/TEMP Water Quality Meter TesterOpens in a new window or tabPre-Owned$13.99erarms_3584 (1) 0%0 bids · Time left2d 9h left (Mon, 01:52 AM)$27.00Buy It Now+$3.96 shipping
- 7-in-1 Water Quality Tester Pen PH Tester Bluetooth-Compatible for Water PoolOpens in a new window or tabBrand New$36.39smarthomejmf (697) 96.9%Was: $39.99 9% off+$9.99 shippingfrom China
- GroLine Storage Solution HI70300G Two Sachets (20ml X 2)Opens in a new window or tabBrand New$12.00nutes (6,421) 98.6%Free shipping
- 7 in 1 Water Quality Tester Meter Pen Digital LCD PH/TDS/EC/ORP/TEMP/SG/SalinityOpens in a new window or tabBrand New$23.79Save up to 10% when you buy morellusyhxtt (1,322) 98.4%Free shippingFree returns
- 6in1 Digital Water Quality Tester CL/EC/PH/TDS/ORP Temp APP Meter Detector ToolOpens in a new window or tabBrand New$60.71smartcity541 (476) 99.1%Was: $65.99 8% offFree shippingfrom China
- Water Quality Tester SG PH EC SALT ORP TDS CF TEMP 24 Hour WiFi Monitor US PlugOpens in a new window or tabBrand New$45.25csvtion (1,662) 98.6%Was: $48.14 6% offFree shippingfrom China
- 7 In 1 Water Quality Monitor WiFi For APP EC Conductivity PH ORP Meter New YAOpens in a new window or tabBrand New$54.20 to $54.39yandonsfo (2,295) 96.9%Was: $58.91 8% offFree shippingfrom China
- Milwaukee PH-COMBO Starter Solution Kit for pH and ORP MetersOpens in a new window or tabBrand New$69.99Save up to 15% when you buy moreTop Rated PlusFree shippinggetultimatenow (3,207) 100%Free returns
- 7 in 1 PH/ORP/EC/TEMP/SALT/S.G/TDS LCD Backlight Water Quality Tester MeterOpens in a new window or tabBrand New$23.42modulesworld2022 (2,990) 99%Free shippingfrom ChinaFree returns84 sold
- 7 in 1 Digital LCD PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Tester Meter PenOpens in a new window or tabBrand New$21.43Buy 1, get 1 15% off with coupondexe5290 (1,460) 98.3%Free shipping
- Digital pH/ORP Meter H5502-1, w/ Cosrad Power Cable & Carrying Briefcase, CaseOpens in a new window or tabPre-Owned$19.99atx-liquidators (1,170) 99.6%+$33.59 shipping
- New ListingDigital ORP Meter Auto Calibration High Accuracy Clear Display Portable STOpens in a new window or tabBrand New$24.76auto_park9 (29,795) 98.2%Free shippingfrom China
- PH‑803W PH ORP Controller Acidity Alkalinity Controller Water Quality Monitor USOpens in a new window or tabBrand New$128.92Extra 8% off with couponWas: $137.15 6% offyundet22 (182) 97.9%Free shippingFree returns
- 7 in 1 PH/ORP/EC/TEMP/SALT/S.G/TDS LCD Backlight Water Quality Tester PH MeterOpens in a new window or tabBrand New$25.59Save up to 10% when you buy morecowramill (5,244) 98.5%Free shipping
- PH‑803W PH ORP Controller Acidity Alkalinity Controller Water Quality Tool(US)Opens in a new window or tabBrand New$128.59$7 off every $100 with couponWas: $136.80 6% offcabestdeal (8,884) 98.3%Free shippingFree returns
- RCYAGO 7-in-1 Water Quality Multi-Parameter PH RH EC CF TDS (ppm) ORP TemperaturOpens in a new window or tabBrand New$99.99winterlyn2014 (346) 100%Free shipping
- ORP REDOX Electrode 50 OHM BNC Type Replaceable for ORP Meter Tester MonitorOpens in a new window or tabBrand New$29.99gxproducts (17,408) 100%Free shippingfrom Hong Kong
- 10 in 1 Water Quality Tester PH Meter TDS/EC/Salinity/S.G/ORP/H2/MΩ/Temp TesterOpens in a new window or tabBrand New$30.30 to $31.25diymoremodules (562) 98.7%Was: $32.89 5% offFree shippingfrom China
- Portable 4 In 1 Hydrogen-Rich Test Pen PH/ORP/TEMP Water Quality Meter TesterOpens in a new window or tabBrand New$36.79darupsun (13,734) 97.8%Free shippingFree returns
- 6 in1 Multi-Parameter Water Quality Monitor ORP/pH/EC/TDS/CF/mV/Temp MonitorOpens in a new window or tabBrand New$120.29vetus-instruments (558) 98.7%Was: $133.66 10% offFree shippingfrom China7 watchers
- 7 in 1 Digital LCD PH/TDS/EC/ORP/TEMP/SG/Salinity Water Quality Tester Meter PenOpens in a new window or tabBrand New$22.50fdtele (2,351) 99.1%Free shippingFree returns
- Portable 4 In 1 Hydrogen-Rich Test Pen PH/ORP/TEMP Water Quality Meter Tester YUOpens in a new window or tabBrand New$36.79usseller999 (13,470) 97%Free shippingFree returns
- pH Meter, NIRIAHO TDS Meter 8-in-1 pH Tester PPM Meter EC Meter Salt Tester ORPOpens in a new window or tabOpen Box$22.40emily_varieties (3,316) 96.3%Was: $28.00 20% offFree shipping
- REED Instruments R3000SD Data Logging pH/ORP MeterOpens in a new window or tabBrand New$229.00globaltestsupplygts (2,202) 98.1%+$7.50 shippingFree returns
- Ohaus ST20R ORP pen meter, measurement range -1000mV to 1000mV, temperature disOpens in a new window or tabNew – Open box$99.99dirt_cheap_books (4,327) 100%Free shippingFree returns
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