Master disconnect switch. High amperage capacity: 300A at 12V DC. Protects vehicles against tampering, theft and battery drain. Protects from hazards during vehicle servicing, and can be locked-out or tagged-out. Provides an effective emergency power cutoff. Can be used in both positive or in negative path applications. Waterproof and dustproof to IP67 (immersible). Switch can be located in the best location, regardless of environment. Large divider on base prevents accidental shorting of high energy cables. Fits standard Master Disconnect mounting pattern. Knob is secured in place with a set screw. allow 10-12 days for delivery if out of stock.