Instructions: To turn it on quickly press the middle button. 12V Low-profile Inline Controller Dimmer Switch for Single Color LED Strip Light To enable standard dimmer mode, press the lower button once, then you can press the middle button to increase brightness or press the lower button to lower brightness. Installation is simple, just connect it between the driver and the strip. To enable one of the dynamic modes press the top button. Real colors may slightly differ from the pictures, as it depends on specific monitor settings and light brightness. The speed of the dynamic modes can be adjusted by pressing the middle button. To exit dynamic mode, click the lower button once which switches it back to standard dimmer mode. Retains setting after power loss To turn it off press and hold the middle button. Remote Free LED Brightness Control Buy IEI 12V-24v Max 30A DC Single Color LED Strip Light Dimmer 12V Inline Dimmer Controller Manual measurement, with small error. It can dim any 12VDC LED product from 10%-100% using Pulse Width Modulation (PWM) circuit push button control from stepped intensity adjustment Choose from 8 levels of brightness, turn lights on or off, or choose a dynamic mode for added effect. LED Inline Dimmer - LED Lights Canada Dimensions: 42x12x3mm