I know how to adjust the calibration but you need a standard to assure its set correctly. What do i do?

You may buy the ORP calibration solution for our store, the following is the link, or you may buy the calibration solution from other sellers, you may use 225mV, 256mV or 400mV solution to calibrate your meter. https://www.amazon.com/calibration-solution-Oxidation-Reduction-Potential/dp/B01FS0G8WK/ref=sr_1_fkmr0_1?keywords=ORP+256mv+standard+solution&qid=1558509756&s=gateway&sr=8-1-fkmr0.

What’s the difference between this one which is green and the other one which is red? Is one newer than the other?

The Green one is new design with same function of red one(ORP-002).

Will this work to show the ionization - orp of my invigorated water purifier?

It will show the ORP rating of the water. However, Reduction Potential in water, without adding a supplement comes from splitting apart water molecules with electrolysis, creating negative ionized hydrogen. Oxidation is electron loss. Reduction is electron gain. A standard filter should not affect the ORP very much.. I dont know much about invigorated filter, but alkaline does not necessarily mean reductive.

Does this measure free chlorine levels?

Hi,it can only measures the oxidation-reduction potential (ORP) value of water, cannot measure free chlorine levels.

Fully operational. Shipping worldwide, on schedule.Customs & duties included in the price

Help Track order

Account Cart

Fully operational. Shipping worldwide, on schedule.Customs & duties included in the price

Help Track order

Account Cart

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

Product ID: 76999410

📏Wide -1999 to +1999 mV range

📱Compact, portable & shockproof

🛠️1-point calibration with screwdriver

301 Lei

Duties & taxes included

In stock

Sold byAmazon RomaniaDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to Romania.

Secure transaction

Description

💧 Stay sharp, stay ahead — measure your water’s true potential!

EFFORTLESS CALIBRATION - 1-point calibration with included screwdriver ensures reliable readings without the hassle.
VERSATILE WATER TESTING - Ideal for aquariums, pools, spas, aquaculture, and water treatment systems — stay ahead in water quality management.
BUILT FOR ON THE GO PROS - Compact, lightweight design with shockproof case fits perfectly in your pocket for anytime, anywhere testing.
PRECISION AT YOUR FINGERTIPS - Measures ORP from -1999 to +1999 mV in 1 mV increments for ultra-accurate water quality insights.
SMART TEMPERATURE COMPENSATION - Automatic adjustment from 0–50°C guarantees consistent accuracy regardless of environment.

The ORP Meter offers professional-grade oxidation-reduction potential measurement from -1999 to +1999 mV with 1 mV precision. Featuring user-friendly 1-point calibration, automatic temperature compensation, and a durable, portable design, it’s perfect for aquariums, pools, spas, and industrial water systems. Compact and shockproof, this tester empowers you to monitor water quality anytime, anywhere with confidence.

Specifications

ASIN	B07D12JR8T
Batteries	4 LR44 batteries required.
Best Sellers Rank	#116,630 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #98 in Lab pH Meters
Date First Available	May 11, 2018
Item Weight	4.6 ounces
Item model number	ORP-228
Manufacturer	Gain Express Holdings Ltd
Product Dimensions	6.1 x 1.22 x 0.62 inches

Common Questions

Are the products genuine and authentic?+

Yes, all products are sourced directly from authorized retailers in the US, UK, UAE and India. We maintain strict quality control processes and verify each product before shipping. All items come with applicable manufacturer warranties and are covered by our standard return policy.

How long does delivery take and is it reliable?+

Delivery times vary by destination country, typically ranging from 3-9 business days. Each order is fully trackable through our system. We handle all customs clearance and use reliable courier partners for last-mile delivery. You'll receive regular updates about your order status via email and our app.

What is Desertcart? Is it safe to order from?+

Desertcart is an international e-commerce platform operating since 2014. We securely process thousands of orders globally each day. Every product goes through our quality verification process before delivery, and we provide end-to-end order tracking, 24/7 customer support, and a comprehensive returns policy to ensure a safe shopping experience.

How is product pricing calculated?+

Our prices include the product cost, international shipping, import duties, customs clearance, and local delivery charges. We handle all customs and import procedures, ensuring there are no hidden fees upon delivery. PRO members receive additional benefits including free shipping.

Trustpilot

TrustScore 4.5 | 7,300+ reviews

Neha S.

Excellent communication throughout the order process. Product is perfect.

2 weeks ago

Zainab N.

Fantastic and great service. Shipping was faster than expected.

1 week ago

View all Trustpilot reviews

Shop Global, Save with Desertcart

Value for Money

Competitive prices on a vast range of products

Shop Globally

Serving millions of shoppers across more than 100 countries

Enhanced Protection

Trusted payment options loved by worldwide shoppers

Customer Assurance

Trusted payment options loved by worldwide shoppers.

Desertcart App

Shop on the go, anytime, anywhere.

301 Lei

Duties & taxes included

In stock

Sold byAmazon RomaniaDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to Romania.

Secure transaction

Trustpilot

TrustScore 4.5 | 7,300+ reviews

Farhan Q.

The delivery time was excellent, and the packaging was secure.

2 months ago

Ayesha M.

The product exactly matches the description. Very satisfied with my purchase.

5 days ago

View all Trustpilot reviews