Perko 9601 Series battery On-Off switches are among the most popular battery switches ever produced. Their traditional Perko bolt circle makes for easy installation. These switches can be mounted in numerous locations. And as ignition protected switches, they can be installed in the engine rooms of gasoline powered boats. Versions of the 9601 Series switches offer additional features such as alternator disconnect and key lock security. Battery disconnect switches help manage the overall use of electrical power onboard. They are used to connect or disconnect electrical devices from the electrical system. They help to prevent battery drain during periods of inactivity. They allow for a quick and easy way to shut down the entire electrical system in an emergency. An optional key lock helps to prevent unauthorized use of the vessel. Perko battery switches are designed for surface mounting. Standard duty disconnect switches have bright red polycarbonate reinforced housings for safety with large easy-to-turn black knobs. The housing of the heavy duty switches are red fiber-reinforced polycarbonate. Models with an Alternator Field Disconnect feature offer protection for Non-Unitized Alternators should the switch accidentally be turned to the OFF position with the engine running. High conductivity studs are long enough to handle more than 1 cable and strong enough for torque needed for secure connections. Optional spacer ring (PN 0462DP0RED) allows for the use of larger cables.