250A Brass Blade Battery Disconnect Switch with Plastic Base, Manual Knife Blade Battery Isolator Switch for 12V-24V Car Truck Boat RV

A blade switch does one thing that no key switch can: it shows you the circuit is open. The MT142 is a manual knife blade battery disconnect — brass blade, plastic base, 250A maximum at 12V–24V — for vehicles that spend more time parked than running.

Lift the lever and the blade swings clear of the contact. There is no spring, no barrel and no key, so the position you leave it in is the position it stays in — and anyone walking past can see it.

• You can see it is off — A blade lifts clear of the contact. Nothing has to be trusted or measured — the gap is visible from a metre away, which is what a workshop or a surveyor wants.
• No key to lose — There is no barrel, no spring and no key. The lever holds where you put it, so nothing can be switched back on by someone who finds the vehicle.
• Contacts you can reach — The blade face is exposed. A brass blade that has sat for a season wipes clean with a file or abrasive pad instead of being replaced.
• Nothing to fail quietly — A rotary switch can wear and lose tension without looking any different. A blade either makes contact or it does not.

• Storage and transport disconnect — The classic job: isolate the battery so nothing drains it over weeks in a yard, a container or a showroom.
• Accessory and winch feeds — Single heavy accessory circuits within the 250A maximum, switching them independently of the main harness.
• Small petrol engines — Cranking a small four-cylinder petrol engine sits inside the range. Large diesels need a higher-rated switch.
• Not a load-break device — Never open the blade with a load running. Switch off the consumers, then lift the lever.

• Brass blade and lugs — Brass resists surface corrosion far better than plated steel and keeps a low-resistance face at the contact point.
• Plastic base — The body insulates the two terminals from the mounting surface, so the switch does not need an isolated bracket.
• Check the nuts after fitting — A brass stud and a steel nut expand differently. Re-torque after the first week of service, then at each inspection.
• Keep the pivot free — A drop of light oil at the hinge twice a year keeps the lever firm without attracting grit.

• Short cable runs — Mount close to the battery so the unswitched cable length stays short. Every extra metre is unprotected.
• Fuse downstream — The switch is a disconnect, not a fuse. Protect the circuit that follows it.
• Rigid surface — The lever needs a firm base. A vibrating panel will work the fixings loose and the blade along with them.
• Hand clearance — Leave room to lift the lever fully. A blade that only opens halfway is a hot spot waiting to happen.

MT142, knife blade battery disconnect switch, brass blade on a plastic base, 250A maximum, 12V–24V, manual lever with mounting fixings included. There is no minimum order quantity: single units, samples and mixed containers are all accepted, with pricing quoted against quantity and packing.

Standard production takes 30 days from deposit. Payment by T/T or Western Union, 30% down and the balance before shipment. Carton packed; pallet lots quoted separately.

Send your circuit current, cable size and panel thickness and we will confirm the MT142 configuration, packing and freight. No minimum quantity required.