The Oakton WD-35634-05 EcoTestr pH1 tester is an economical, simple-to-use pH tester that measures pH levels and temperatures quickly, displaying them both simultaneously on a large dual-line LCD. It has a pH range from 0 to 14 with an accuracy of ±0.1 pH. The tester features up to 3 pH calibration points with auto NIST and US buffer recognition.|Additional features of the WD-35634-05 include a long-lasting durable electrode with polymer reference electrolyte; status icons for measurement stability, calibration, and battery life; and self-diagnostics. The IP67-rated housing features an easy-to-grip design and floats if accidentally dropped in water when sensor cap is on. The tester, powered by 4 AAA batteries, can operate up to 400 hours continuously. The unit will auto power-off after 8 minutes of non-use to conserve power.