SEARON Agrigarden Machine Digital Tach Hour Meter Tachometer Voltmeter Volt Meter for Tractor Cultivator ATV Trailer Sprayer Compressor Robot Milking Trimming Waterproof digital Hour Meter and Tachometer with Voltmeter 3 in 1 for Tractor Cultivator ATV Trailer Sprayer Compressor Robot Milking Trimming External 5-65 Volt DC power to supply the meter Internal CR2032 battery works only when the external power is off Tachometer with Max RPM record and Overspeed alarm, Voltmeter with Overvoltage and undervoltage reminder Dust proof / Water proof Rating: IP68. With CE & RoHS Certification and 1 Year Warranty