The Master Battery Disconnect Switch is designed to cut off the power flowing to the battery to prevent unauthorized use of your vehicle or unwanted battery drain when it is not in use for extended periods. This switch fits the slightly smaller negative terminal of all standard-sized automotive batteries. Ideal for cars, boats, trucks, RVs, and more. This extremely convenient cut-off switch allows you to quickly and easily disconnect your car battery for safety, maintenance, or storage. Easy to install and simple to use. To turn on the power, simply tighten the green knob and slightly loosen the green knob to disconnect all power. Weight: 120g. Product Description Spurtar Top Post Disconnect Switch for Marine, Boat, RV, ATV, Motorcycle, Car, Van, Boat Description: Battery master disconnect switch mainly used to solve the problem of leakage and loss of electricity. caused by batteries that are not used frequently in car, boat, motorcycle and car batteries. Features: Used for top post, connected to the battery negative column 15-17mm only. Voltage: 12V, Rated Current: 125A. Easy to install and simple to use. Release/twist is off, tightening can be conductive. Made of copper-plated zinc alloy, rust and corrosion resistant, durable for safe use. Prevents battery drain when storing and repairing cars and trucks. Fits on motorcycle, car, van, boat, also on electrical equipment switches. Product Dimensions: 8.5 x 3.8 x 3.8 cm. Compatible with all standard round-sized batteries. Package Included: 1 x Battery Master Disconnect Switch. 1 x Nut and Bolt.