2pcs Portable Pen Type Digital Water Quality TDS pH Tester Battery Powered Measurement Detection Water Purity Monitor for Aquarium Pool Specification: Material: ABS plastic shell TDS detector size: 155*25*14mm Power supply: 2*LR44 button battery Test item: TDS value Measuring TDS range: 0-9990PPM Resolution: 1PPM Error: ±2% PH detector size: 155*30*15mm Power supply: 2*LR44 button battery Operating temperature: 0-80℃ Test item: PH value Measuring range: 0.0-14PH Resolution: 0.01PH Error: ±0.05% Applicable industries: Households, hospitals, swimming pools, disease control centers, water plant laboratories, aquaculture Color: A White TDS Tester + White pH Meter, B Blue TDS Tester + Yellow pH Meter Note: Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you! Please allow 1-2cm measuring deviation due to manual measurement. Included: 1 X pH Detector 1 X TDS Detector