How to Use: 1. Remove the protective hat, wash the electrode with distilled water or tidy water, and then wipe off the water on the electrode and the plastic parts around the electrode with filter paper (do not touch the electrode with your hands). 2. Start the meter, immerse the electrode in the solution to be measured, and start the measurement. Please read the manual for details Specification: Item Type: Dissolve Hydrogen Meter Material: ABS Size: Approx. 20.7 x 3.6 x 3.2cm / 8.2 x 1.4 x 1.3in Weight: Approx. 156g / 5.5oz Range: ppb: 0-1999ppb / ppm: 0-1.99ppm Resolution: ppb: 1ppb / ppm: 0.01ppm Accuracy: ppb: ±10ppb / ppm: ±0.02ppm Automatic Temperature Compensation: 0℃~50℃ Battery Information: 2 x AAA Battery 1.5V(Battery Not Included) Working Temperature: 0℃~50℃ Package List: 1 x Dissolve Hydrogen Meter 1 x User Manual