Milwaukee Instruments, MW804, MAX Waterproof 4-in-1 pH / EC / TDS/Temp Tester with Replaceable ProbeMW804 Includes Only:Battery 4 x 1.5VMW804 TesterThe Milwaukee MW804 MAX Waterproof 4-in-1 pH/EC/TDS/Temp Tester is designed as an all-in-one solution for growers. The MW804 MAX 4-in-1 tester is accurate to ±0.05 pH, EC/TDS to 2% Full Scale and ±0.5°C / ±1°F for temperature. With automatic calibration and 5 memorized calibration points, the tester can be quickly and easily be calibrated to a higher accuracy compared with manual calibration. The tester comes with a replaceable pH probe with a double junction probe design for longer life. An exposed temperature probe is located close to the pH probe for fast temperature compensation No more worries about dropping your tester while measuring. The MW804 MAX is fully waterproof to IP67. At just 3.5 ounces, the MW804 MAX is easy to handle at up to half the weight of other testers. A large dual level LCD screen makes reading results easy while a stability indicator and hold function that freezes the display takes the guess work out.Features:Fast easy to read results with large digital dual LCD readout.Extreme accuracy to ±0.05 pH, EC / TDS 2% Full Scale and Temperature ±0.5 C / ±1 F.Range 0.00 – 14.00 pH, EC 20.00 mS/cm, TDS 0 - 10.00 ppt, Temperature: 0.0 to 50.0 C / 32.0 to 122.0 F.Lightweight and portable at just 3.5 ounces.Easy measurement: just place the probe in the sample, gently stir, wait for the stability indication to show a stable reading and then freeze the reading.Simple push button, automatic one or two-point calibration with 5 saved calibration points.Gel-filled, double junction pH electrode for low maintenance and high performance.Auto shut off and low power demand for approx. 100 hour of continuous use (batteries included).