Feature: 1. - Quality Material: Made of quality ABS material, more High quality. 2. - Backlight Display: Does not affect the use in the dark. 3. - Waterproof: IP55, meet daily testing requirements. 4. - Data Hold: Data recording, convenient for measurement. 5. - Replaceable Electrode: High cost performance. 6. - Wide Application: Suitable for the measuring of drinking water, hydroponics, aquarium, swimming pool, etc. Specification: Features: - Quality Material: Made of quality ABS material, more High quality. - Backlight Display: Does not affect the use in the dark. - Waterproof: IP55, meet daily testing requirements. - Data Hold: Data recording, convenient for measurement. - Replaceable Electrode: High cost performance. - Wide Application: Suitable for the measuring of drinking water, hydroponics, aquarium, swimming pool, etc. Specifications: Material: ABS Color: Grey+Green Power Supply: 4 * 1.5V AG-13 Battery (Not Included) Operating Temperature: 0~50℃(32-122℉) Measurement Range: -1999~1999mV Resolution: 1mV Accuracy: ±5mV Item Size: Approx. 19*3.8*3.8cm / 7.48*1.5*1.5in Item Weight: Approx. 67g / 2.36oz Package Size: Approx. 25*10.5*5cm / 9.84*4.13*1.97in Package Weight: Approx. 143g / 5.04oz Note: Please read the Users Manual before use. Packing List: 1 * ORP Tester 1 * Screwdriver 1 * Users Manual(English) Package List: 1 * ORP Tester 1 * Screwdriver 1 * Users Manual(English)