pack of 2, outdoor hard-wired post eye light control electric resistor photocell light sensor, dusk to dawn sensor, convert fixtures to auto on at night, led hid cfl jl-103a creative hobbies pack of 2 photoelectric switches for one low price! 3 year warranty! functions as a light sensitive switch that will turn off devices in the presence of light and turn them back on in the absence thereof. ideal for wiring into a lamp or lighting system requiring photoelectric automation. provides security by discouraging intruders through automatic lighting of property at night. perfect replacement photocontrol for pole lanterns, yard lights, twin floodlights, area lights, entry lights, walkway lighting, and barn lights. will increase energy efficiency and bulb life by reducing daily operating life. time delay prevents interference from flashes like headlights, lighting, etc. works with cfl, incandescents, mercury vapor, metal halide, sodium vapor, led, halogen and fluorescent bulb.