Applicable to the negative diameter of the battery of the 12V / 24V car battery of 15-17mm. To prevent the car from consuming battery power, facilitate temporary power off during vehicle maintenance. Extend the life of the car battery head. Made of brass, corrosion resistance, good conductivity. The maximum current up to 800A, the rated current of 150A. Simply lift the knife and the power is cut off. The battery disconnect switch prevents short circuits and fires when working on electrical systems. Can be adjusted by the bottom of the screw, into a vertical knife switch or a horizontal knife switch.