Brass Knife Blade Master Switch

Straight forward to install (on the negative terminal). This (pictured) version is for battery posts on the side of the battery. The only tool needed was a socket wrench (15mm socket for the included bolts). We use it to prevent phantom battery drain in a vehicle kept at a vacation home that we visit every 3-4 months. Construction of the switch is sturdy and the knife-blade is held very firmly by the receiving clasp when the circuit is closed--it will not open on it's own through vibration/driving. This could be used as an anti-theft deterrent to prevent ignition hot-wiring, but if the would-be thieves opened the hood, they may identify it...of course one could extend the negative run and hide this in a less visible location, but more often then not, they don't take their time when trying to steal vehicles and would likely move on without even opening the hood, so, in my opinion this doubles as a cheap, (reasonably effective, but easy to defeat if found) anti-theft device.

I have these in my three Jeep Wranglers. Perfect for quick battery disconnect when doing auto repair work.

Installed easily works just as described in a camper situation. No evidence it would break easily as other complained. I turn it off and on often, seems well made.

I purchased the side mount style for use on an RV/Marine battery with top screw terminals. I used a stainless steel nut and washer to secure to the negative stud, then replaced the supplied bolt with a stainless steel bolt and nut to secure the RVs ring terminal wires. Works perfect and much heavier than I expected.

I am constantly disconnecting the battery on my 2012 Corvette for maintenance and electrical work/repair. This device is perfect, as it allows me to disconnect the negative terminal with a flick of a switch. Also, if I’m going to be away from home for some time, I can disconnect to avoid battery drain-down. It’s a well made device that compliments my engine and accessories.