Feature: 1. Function: Dual battery selector switch can switch isolated battery packs to all loads or combine battery packs to all loads, make before break contact design allows switching without interrupting power. 2. Current: The 300A continuous rating is safe for installation on gasoline powered boats and the 400A intermittent rating is the maximum amount of current that can be loaded for a specified minimum period of time. 3. For Use with 2 Batteries: Isolator switch allows selection between batteries for starting and charging or operation of both in parallel. This switch can be used with 6‑32V. 4. Universal Application: Dual battery disconnect switch is universal, can be widely used for marine, boat, RV, big truck, modified car. 5. 15mm Studs: Nickel plated copper studs for maximum conductivity and rust resistance, studs can accept M8 ring terminals, 15mm stud length accepts multiple cable terminals. Specification: Item Type: Battery Selector Switch Material: Nickel plated, copper Switch Position: 4 (OFF-1-BOTH(1+2)-2) Battery Combo: Yes Working Voltage: 6-32V DC Continuous Rating: 300A Instantaneous Current at Startup: 400A Number of Binding Posts: 3 Terminal Size: M8 Terminal Length: Approx. 15mm/0.59in Function: Make before break contact design allows switching between battery packs without interrupting power Application: Suitable for Marine, Boat, RV, big truck, modified car. Package List: 1 x Battery Selector Switch3 x Plug