Labtron portable pH/ORP Meter for field and laboratory water quality measurement. It measures pH (0.00–14.00, ±0.01 resolution) and ORP (−2000 to +2000 mV), with millivolt and temperature outputs. Automatic multi-point calibration, NIST buffer recognition, and temperature offset adjustment support accurate readings across drinking water analysis, wastewater testing, environmental monitoring, and aquaculture applications. Backlit LCD with data hold included