1) The meter has positive and a negative leads for easy installation. 2) The timer has a 6 digit display with the least significant digit being 1/10 hour (99999.9) and operates on input voltages from for DC Volts 12-36 for DC. 3) The hour meter timing mechanism contains a quartz oscillator which provides a of accuracy. Condition: Voltage: for DC 12V-36V Power: 0.3W Use Temperature: -10°C -50°C Suitable for: Tracking on machinery such as boats, for cars, trucks, or any other device where is used to determine oil change intervals, service requirements or where there is a need to record hours operated Note: The item without "automatically to zero" function Color: As Shown Material: Metal+Plastic Package Contents: 1 x Professional round hour meter Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.