Another component of the Aeromarine Radio Box System. Simply bore a 3/4" hole in your Radio Box lid near your receiver switch, insert our Radio Box Plug and flip over the lever to completely seal. Remove to access your switch. Use a switch with a charge jack to charge your rechargeable batteries and you seldom need to take off your lid. Keep plug out when not using your hull to allow any condensation to vent out of your radio box.