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COZYEHOO

Side Post Knife Blade Master Switch 12V 24V Battery Disconnect Cut Off Shut Off for Auto Car RV-Marine Boat Truck Vehicle

  • Based on 1,794 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Thursday, Jul 9
Order within 9 hours and 26 minutes
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Style: Side Post


Features

  • COMPATIABLEThis knife-blade battery disconnect switch is suitable for SIDE POST TERMINAL, battery Negative post only. Maximum Current: 750A, Rated Current: 250A. 6v 12v 24v car truck, bus, RV, Boat, trailer battery
  • TOP LEVEL & HEAVY DUTY This side post battery disconnect switch is made of brass material, corrosion resistance, conductive performance is good, durably made for safety use
  • EASY TO INSTALLThis battery doctor knife switch for side post easy to install & simple to use. Switch the knife, then power will cut
  • SAVE ELECTRYCITYThis knife blade master switch is used for the battery to isolate and secure the electrical system, eliminate any power draw from the battery when vehicle or boat is not in use, stop unwanted battery drain and prevent theft or unauthorized use.Widely used for car, truck, boat or RV battery, also other electrical equipment's battery
  • BUY WITH CONFIDENCE: We are so confident you'll think we have the satisfied battery disconnect switch on the market. If you have any problem about our product, please feel free to give us a message and we will do anything for you to make the thing right. We go out of our way to make sure every customer is happy and satisfied with our product and service.

Operation Mode: Off


Current Rating: 200 Amps


Operating Voltage: 24 Volts


Contact Type: Normally Closed


Connector Type: Plug In


Brand: COZYEHOO


Switch Type: Mechanical


Material: Brass


Item dimensions L x W x H: 3.7 x 3.7 x 0.8 inches


Circuit Type: direct-current


Operation Mode: Off


Current Rating: 200 Amps


Operating Voltage: 24 Volts


Contact Type: Normally Closed


Connector Type: Plug In


Switch Type: Mechanical


Circuit Type: direct-current


Mounting Type: Surface Mount


Actuator Type: Hinge Lever


Number of Positions: 2


Upper Temperature Rating: 250 Degrees Celsius


Control Method: Touch


Connectivity Protocol: X-10


Wattage: 6 watts


Compatible with Vehicle Type: Car, Truck, Bus, RV, Boat, Trailer


Control Type: Manual


Compatible Devices: Car, Truck, Bus, RV, Boat, Trailer, Other Electrical Equipment


Item Dimensions: 3.7 x 3.7 x 0.8 inches


Unit Count: 1.0 Count


Number of Items: 1


Material Type: Brass


Contact Material: Brass


International Protection Rating: IP65


Brand Name: COZYEHOO


Model: sd02


Manufacturer: COZYEHOO


UPC: 616430854368


Part Number: sd02


Item Weight: 0.01 Ounces


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Jul 9

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

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Top Amazon Reviews

    • Works on my pickup truck
Style: Side Post
I do wish it came with better instructions .Installed on my pickup truck . Works awesome. Easy to connect and disconnect everytime I use my truck.
Reviewed in the United States on March 11, 2026 by tanya
    • Works great
Style: Top Post (Vertical)
Installed on my car and it works great. Easy to install
Reviewed in the United States on April 3, 2026 by Robert S.
    • Quality
Style: Top Post (Vertical)
High quality great value
Reviewed in the United States on April 21, 2026 by Randy
    • Great tool for prolonging battery life
Style: Side Post
Car batteries have near doubled in cost within 5 years. And the worst thing you can do to a battery is let it drain down to dead. If you have a vehicle that sits a lot, I highly recommend to either disconnect the battery or to take the time to charge it occasionally. That brings me to this product. I've used it twice now, once on a top mount and then this one on a side post mount. Here's my takeaway. The mechanism can be disassembled to arrange either the lever or the battery post mount on either side. This mechanism is fairly big. If you have a top mount, make sure there is ample clearance when closing the hood. Id say a good 2 inches is needed from the top of the battery to the bottom of the hood for this to clear. This side post version doesn't protrude up or out as far as the top post mount version making it slight easier to install and for clearance. I had to free up some length on my negative battery terminals to reach the new location of where it screws to this. It only makes it a few inches further of a reach but it was enough to make my cable too short. Thankfully, the fix was only to only pop off one cable retainer about a foot below the battery terminal. That let me route the battery cable at a slightly different angle and freed up a few inches in length. Things that could be better; The plastic bracket that both the lever and the post mount to is fairly flimsy. It's not a solid piece of plastic as I feel it should be. It's hollowed on the back side. I wouldn't be surprised if it breaks over the course of several years. It definitely could be designed slightly smaller. The allen head bolt and locking nut that act as the hinge pin for the lever was very loose. The nut was a dozen turns away from being tight. This bolt / nut set the tension on the lever arm, tighten accordingly. Each side of this mechanism has a Phillips head bolt that secures the post mount and the lever arm to its plastic bracket ( the one I feel should be a solid piece ) The tread contact points for this connection is dismal. Its the equivalent of threading a machine screw into a thick piece of sheet metal. I would highly recommend adding thread locker to those bolts. All in all, this thing is cheap and it's construction reflects it. Nevertheless, it's cheap insurance and a great tool to help prolong the life of a recreational vehicles battery. Don't hesitate to work with it to make it a little better or fit better for your application. But be gentle to some degree. Others have mentioned they've broken it during install. I could see that but I'd still put that back on them for being too forceful. If you have a vehicle that doesn't get driven much and you have a little bit of mechanic knowhow, give it this a shot. But don't set expectations too high. It works, it does., but yes, it could be better. ... show more
Reviewed in the United States on March 18, 2024 by a.p
    • Excellent Battery Disconnect
Style: Top Post (Horizontal & Vertical)
Simple and uncomplicated - dependable and reliable.
Reviewed in the United States on March 17, 2026 by Charles L. Smith
    • Works great
Style: Top Post (Vertical)
Works great
Reviewed in the United States on April 27, 2026 by Gene N.
    • Saves car battery ๐Ÿ”‹
Style: Side Post
Perfect for my car ๐Ÿš— that sits for a long time, so the battery ๐Ÿ”‹ doesn't drain.
Reviewed in the United States on April 11, 2026 by Edward M.
    • 4 Year Lifespan 4 Year Lifespan
Style: Top Post (Vertical)
Review Image by Randy
This master switch did its job for 4 years before the locking nut holding the knife blade portion finally gave out. I noticed my dashboard kept lighting up like a Christmas tree every time I hit a bump, so I went home and checked my battery voltage with a multimeter. The readings were as follows: 14.1V while running and 12.0V while the engine was turned off. After inspecting the battery closer, I disconnected the switch one last time and the knife portion of the master switch came off with it. I respect the okay build quality and this device served its purpose, but donโ€™t expect this device to last more than 4 years. You get what youโ€™re paying for. You will have to replace it eventually. ... show more
Reviewed in the United States on May 3, 2026 Reviewed in the United States on May 3, 2026 by Randy

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