Easy setup. All you need is a 3/4 inch (19mm) hole and the switch will sit in nicely;no more square cut outs.Our switch comes with a kyhole slot to prevent unwanted rotationSPST 2 pole design (On/Off) 3rd poles with LED to be connected to earth.Functions: It can be applied as the switches for the additional electronical equipment inside&outside the car.(such as flashing lights,chassis lights,and dome lights)Condition: 100% Brand NewColor: Black and BlueMaterial: plasticLight color: Blue LED lightSize: 2.3*2.5cmQuantity: 1 pcRating: DC 12V 20AType: 3 PinsSPST: ON-OFFNote:1. Instruction is not included,professional installation is highly recommended.2. Please check the size measurement chart carefully before making payment.Package Contents:5pcs Blue LED light Round Switch(waterproof)Only the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.