Battery disconnect switches control electrical supply to the vehicle allowing vehicle to be shut down in the event of an emergency or to secure vehicle when not in use. Disconnects are offered as a single pole version and a double pole with two separate circuits for vehicles equipped with an alternator. Single Pole Disconnect has two terminals and is recommended for vehicles not using an alternator that need ability to be shut down in the event of an emergency or when securing a vehicle by shutting all power off to the vehicle. Note: When attempting to shut down a vehicle with an alternator using a single circuit battery disconnect, the alternator may continue supplying power to the vehicle ignition system allowing vehicle to continue to run. Double Pole Disconnect has four terminals with two separate circuits which is recommended for a vehicle with an alternator that needs to be shut down in the event of an emergency. Standard Duty Switch with Decal - Standard duty switch mounts in a 3/4" hole in a panel up to 1/4" thick and includes a decal to indicate On/Off position. Switch has 3/8"-24 terminals and is rated at 175 amp continuous duty. Double pole switch also has 10-32 studs rated at 20amp continuous duty. Severe Duty Switch with Decal - Severe duty switch mounts in a 3/4" hole in a panel up to 1/4" thick and include a decal to indicate On/Off position. Switch has 1/2"-20 terminals and is rated at 300 amp continuous duty and is sealed to resist weather and help prevent internal corrosion. Double pole switch also has 10-32 studs rated at 20amp continuous duty.