Hour Meter, Display Type Electromechanical, Time Range 0 to 99999.9, Bezel Face Size 2.50 in dia, Bezel Face Shape Round, Bezel Face Type Flush Mount, Elapsed Time To 9,999.9, Operating Voltage 10 to 80V DC, Hz -, Number of Digits 6, Display Units Hours/Tenths, Bezel To Back Length 2.89 in, Depth 2.89 in, Ambient Temp. Range -40 Degrees to 185 Degrees F, Material of Construction Black Polymer, Input Type -, Reset Type No Reset, Temp. Range -40 Degrees to 185 Degrees F, Fits 2.0 in dia Opening