Feature: 1. Stored Synchronously Data: The ORP meter can share data or print forms, keeping time and data records synchronously. 2. Backlit Control: This digital display ORP meter supports backlit control, long life and excellent performance. 3. BT Function: Using sophisticated production technology, it has BT function and supports BT control data recording. 4. Wide Uses: Suitable for conventional aqueous solutions, can be used in swimming pools, spas, hydroponics, environmental monitoring, laboratories, etc. 5. Replaceable PH Probe: The ORP meter uses a high quality replaceable PH probe, which is strong, durable, and not easily damaged. Specification: .Item Type: ORP Meter Material: ABS ORP Range: -999mV to +999mV Resolution: 1mV Temp. Range: 0.1℃ to 60.0℃, 32.1℉ to 140.0℉ Resolution: 0.1℃, 0.1℉ Accuracy: ±1℃ Calibrated ORP: 256mv Temperature Compensation (ATC): 0.1℃ to 60.0℃ Working Environment: 0.1℃ to 80.0℃, RH: Maximum 90% Battery: 3 x 1.5V LR44 (Battery Not Included) Product Size: Approx. 187 x 37 x 37mm / 7.4 x 1.5 x 1.5in Weight: Approx. 158g / 5.6oz Package List: 1 x ORP Meter (Battery Not Included)1 x User Manual Note: Rinse the electrode with distilled water between each use, keeping the ORP electrodes moist. If it is not used for a long time, it should be rinsed and stored in a soaking bottle with soaking solution.