Littelfuse anti-theft battery master switch is available in two versions, fused and detachable. Fused version maintains current or all electrical circuits such as the alarm, on board computer, central locking system and radio memory presets. Detachable version features a special disconnect that allows the battery to easily be removed for anti-theft protection. Perfect for seasonal storage needs or easy off vehicle battery charging for autos, motorcycles, RV's and boats. A simple turn of the knob isolates the battery and renders the vehicle unstartable. Makes anti-theft protection affordable when compared to expensive alarm systems. Eliminates complicated installation, no special electrical or mechanical expertise required. Fits all standard top mount post batteries. Can be used with side mount post batteries by using a top mount adapter post (not included). Works on 12 to 24 volt systems up to 135 amperes.