1.LCD shows both pH & temp.. 2.Compact size, light weight. 3.Auto power off 4.Easy to change the pH ... buffersBuild in temperature sensor, ATC (auto temperature compensation)Compact size, light weightThree point calibration for pH 4.01, pH 6.86 ... ) x 4 PCsMeter with pH electrode. PT-6021A PH meter ,light weight pH meter