Twistlock Photocell | Dimmable: Non-Dimmable ; Operating Temp: -20c (-4f) to a Maximum of +45c (+113f) ; Nsf Approved: Yes - Approved | Features: Electronic Photocell, Zero-Cross Technology, Led Fixtures Totaling 2220 Wtt @ 277 Vac, Non-Drifting Silicon Light Sensor Ir Filtered, Fail Mode: On | Features: Energy-Efficient Mechanical Timers Do Not Require Electricity to Operate, Automatically Limit the on Times, Press-on Knob Design Ensures Quick and Easy Installation, Cfl Compatible, Provide Direct Replacement of a Standard Wall Switch in Single oFurbay Electric Supp