With removable key, additional function that allows you to activate only certain accessories such as the bilge aspirator, water level, and fuel level, without powering the entire system. Watertightness is guaranteed by a cap that closes the key inlet. The additional function cannot be activated by mistake because the key must also be pressed to turn it counterclockwise. Universal for both petrol and diesel engines, nylon casing, stainless steel + nylon + rubber cap.