With bulit in sensitive dusk to dawn sensor of light socket, the lights will automatically turn on at dusk and turn off at dawn; say goodbye to the hassle of manually controlling the lights, improve energy efficiency. This light sensor socket comes with a retractable spring contact design, you can screw it back after tightening it, adjust the light sensor to face to the sun's direction. 2 mm spring telescopic range, as long as the screwing back range is within 360°, the direction of the sensor can be adjusted at will, and there is no need to worry about looseness or loose contact. No wiring or programming needed, just turn off the power and screw the bulb into the lamp socket; standard E26/E27 base, compatible with LED, CFL, incandescent and halogen bulbs for a wide range of applications. Color: Black 4 Pack.