Meter - Elapsed Time: Type - Elapsed Time Panel Meter; Measurement Application - Electrical Equipment On Time; Indication Scale - Hours; Maximum Indication - 99,999.9; Movement - Synchronous Clock Motor; Display Type - 6 Digit; Reset - No Reset; Operating Voltage - 120V 60 Hz; Enclosure Material - Black Phenolic, Glass Window; Operating Temperature - -4 to 149 deg F (-20 to 65 deg C); Face Dimensions - 3.50" (88.9mm) Diameter; Mounting Opening - 2.82" (71.6mm) Diameter; Mounting Depth - 2.55" (64.8mm); Manufacturer Series - 55ET