.Vertical Knife Negative Battery Disconnect Switch Master Cut Off Isolator

Easy Installation: Vertical type battery disconnect switch, switch the knife, then power will cut, easy to install and use. Item Type: Battery disconnect switch. 1 x Battery Disconnect Switch. Function: Used for battery isolation and protection of electrical systems, eliminating any power drain from the battery when the vehicle or boat is not in use, safely disconnecting the battery.

eBay