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ORP Meter, ORP Redox Meter Tester -1999~1999mV, 1-Point Calibration, Oxidation Reduction Potential, Aquariums, Swimming Pools, Water Treatment Systems, Aquaculture, Spa

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Availability: In Stock.
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Arrives Thursday, Oct 22
Order within 22 hours and 10 minutes
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Color: ORP Redox Meter


Features

  • User-Friendly Design: Large, clear display for easy reading, 1-point calibration with included screwdriver, and automatic temperature compensation (050C).
  • Portable & Durable: Compact, includes a shockproof case. High Accuracy & Affordability.
  • How to calibration: Clean the electrode and gently dry with paper towel. Dip the electrode into the distilled water for about 5 minutes. Turn on the unit by the ON/OFF switch, it is located on top of the unit.
  • Wide Measurement Range: Accurately measures ORP (Oxidation-Reduction Potential) from -1999 to +1999 mV in 1 mV steps, suitable for testing drinking water, pools, aquariums, wastewater, and industrial applications.
  • Experience the convenience of our mini-sized pH meter, carefully designed to fit in your pocket effortlessly. With its compact size, you can now take measurements anytime, anywhere. Whether you're at the pool, on a trip, at the beach, or camping, this portable pH meter is your reliable companion for accurate testing.

Description

We are a high-tech enterprise offering independent development, design, production, and sales of top-quality instrumentation globally Gain Express is a manufacturing and trading company that researches and produces high-tech & high-quality products, and offers a wide range of electronic products & testing instruments. Gain Express has years of trading experience (B2B & B2C) with many customers from North America, South America, Asia, Australia/Oceania, Europe, Africa, the Middle East and so on. Measures the oxidation-reduction potential (ORP) of water in the range -1999 ~ ± 1999 mV in steps of 1 mV. Its advantage is high accuracy and large clear display. Large and easily readable numbers will especially help people with impaired vision. An inexpensive and practical device will be useful in everyday life. At 650 mV, water is unsuitable for bacteria and viruses, and drinking water values of 750 minvolt and above ensure that such water does not contain harmful to human health organisms. Determine the water quality indicators with this ORP meter in just a few minutes - from household to laboratory and industrial (drinking water test, in aquariums, artificial reservoirs, wastewater), swimming pools, water treatment systems, aquaculture, spa, etc.

Product Dimensions: ‎6.1 x 1.22 x 0.62 inches


Item Weight: ‎4.6 ounces


Manufacturer: ‎Gain Express Holdings Ltd


Item model number: ‎ORP-228


Batteries: ‎4 LR44 batteries required.


Date First Available: ‎May 11, 2018


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Oct 22

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

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Top Amazon Reviews


  • Value for money.
I have used orp meter with several brands in the past. When i discovered a pen type orp was available. I had to get one and test it. My pool is 12,000 gallons and i just upgraded my plumbing to maximize flow rate of my ozone system. I was happy to get an accurate reading of 543 mv above the acceptable range. Thanks to this pen type No more guessing. I place the water sample in a glass and let the reading settle for a few minutes. The only drawback shipping is too slow. I wish the Manufacture speed up the shipping. Customers generally Don't mind paying a bit more for fast speed shipping included in the total cost. Orp levels (application) Aquaculture 150-250 Cooling towers 250-350 Swimming pool 400-475 Hot tub 450-600 Water disinfected 600 ... show more
Reviewed in the United States on May 26, 2019 by Michael D.

  • Great ORP Meter. I use this frequently to measure my hydrogen water bottle function. Works great!
ORP for good Hydrogen water bottle should be between -700 to -200, and this Meter helps me monitor that. Easy to use and simple. Be careful when opening the battery compartment, the wires are short but if you are careful no problem.
Reviewed in the United States on March 1, 2024 by R. Bruno

  • Very portable
I liked the size of the tester. Not sure how accurate it is but it gives me a good idea of what the ORP IS.
Reviewed in the United States on February 19, 2022 by Mac

  • Wildly inaccurate and inconsistent
After soaking the probe in distilled water for 2 hours per the instructions and calibrating with their separately sold calibration solution (inital calibration was over 200mV off), reading was over 100mV different after rinsing, drying, and putting back into the calibration solution. Useless for hydroponics and you get what you pay for. Guess I'll just have to pony up and buy a name brand meter. ... show more
Reviewed in the United States on October 27, 2023 by KillaZap

  • Gain Express orp / redox meter tester
This product works exactly as described. It works great for all my freshwater aquariums. An excellent product at a very good price. It arrived on time and in excellent condition.
Reviewed in the United States on January 13, 2024 by John Manrow

  • It works
For less price than others it works very well.
Reviewed in the United States on August 18, 2024 by S. Lampe

  • Needs calibration
Nice size but never worked correctly. Needs constant re calibration using a $12 extra solution. Now don’t trust the readings. Would not recommend due to hassle involved with use.
Reviewed in the United States on August 15, 2021 by Erhwa2

  • Good for the price point
This is a good measuring device for someone that doesn't want to spend a bunch of money on an ORP meter however would like to know just how "charged" their health liquids (water, juices, etc) actually are. It's downside is that the measurement can sometimes take several minutes to equalize. Solid product otherwise. ... show more
Reviewed in the United States on June 7, 2020 by Joel

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