HI981408 has been specifically designed to address the needs of growers in hydroponics, greenhouses and nurseries. The meter has all the features necessary to check the pH of the fertilizer solution during preparation. With a sturdy body, it also floats so that it can be quickly retrieved if accidentally dropped in the tank. Frequent battery replacement is no longer an issue, the HI981408 will run for 2000 hours continuously on common AA-type batteries. This translates into more than 2 years of continuous use up to 2 hours a day, seven days a week! Calibration has been simplified to one point through a dial on the front of the meter. The outer casing also incorporates a molded eye so you can hang the meter when not in use. HI981408 is supplied with spare pH electrode, pH 7 buffer solution, batteries and instructions. 0.0 To 14.0 pH range. 0.1 pH resolution. +/-0.02 pH accuracy . Manual at 1 point calibration. Spare pH electrode, 240mm (9.4") long with double junction and DIN connector included. 2 x 1.5V battery. Approximately 2000 hours of continuous use life. 0 to 50 degree C (32 to 122 degree F), RH 95 percent environment. Measures: 3-25/64" length x 3-11/16" width x 1-19/64" height. Weight: 150 gram.