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Gain Express

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

  • Based on 266 reviews
Condition: New
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$35.90 Why this price?
Save $104.10 was $140.00

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Availability: Only 1 left in stock, order soon!
Fulfilled by Gain Express
Arrives Jul 9 – Jul 22
Order within 4 hours and 1 minute
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Color: ORP Redox Meter


Features

  • 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.
  • Measurement range: -1999 ~ 1999 mV, automatic Temperature Compensation (ATC): 0~50C.
  • 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.
  • Best for household to laboratory and industrial (drinking water test, in aquariums, artificial reservoirs, wastewater), swimming pools, water treatment systems, aquaculture, spa, etc.
  • Package include: 1 x ORP Meter, 1 x Mini Screwdriver, 4 x AG13 button battery, English User Manual

Is Discontinued By Manufacturer ‏ : ‎ No


Package Dimensions ‏ : ‎ 7.13 x 2.52 x 1.26 inches; 4.64 ounces


Item model number ‏ : ‎ ORP-228


Batteries ‏ : ‎ 4 LR44 batteries required.


Date First Available ‏ : ‎ May 11, 2018


Manufacturer ‏ : ‎ Gain Express Holdings Ltd


Best Sellers Rank: #68,553 in Industrial & Scientific (See Top 100 in Industrial & Scientific) #117 in Lab pH Meters


#117 in Lab pH Meters:


Customer Reviews: 4.1 4.1 out of 5 stars 266 ratings


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Jul 9 – Jul 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

    • Great ORP Meter. I use this frequently to measure my hydrogen water bottle function. Works great!
Color: ORP Redox Meter
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
    • Gain Express orp / redox meter tester
Color: ORP Redox Meter
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 A Manrow
    • Very portable
Color: ORP Redox Meter
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
    • Value for money.
Color: ORP Redox Meter
Review Image by Michael D. Michael D.
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. Michael D.
    • Wildly inaccurate and inconsistent
Color: ORP Redox Meter
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
    • Needs calibration
Color: ORP Redox Meter
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
    • Nice
Color: ORP Meter + Calibration Powder
Works fine
Reviewed in the United States on June 11, 2023 by leshueone
    • Great so far
Color: ORP Redox Meter
Works as advertised. Good price.
Reviewed in the United States on April 12, 2023 by Alexander H. Budny

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