--- product_id: 225216885 title: "Top Post Knife Blade Master Switch 12V 24V Battery Disconnect Cut Off Shut Off for Auto Car RV-Marine Boat Truck Vehicle (Negative,Vertical)" brand: "cozyehoo" price: "£17.69" currency: GBP in_stock: true reviews_count: 8 category: "Cozyehoo" url: https://www.desertcart.co.uk/products/225216885-top-post-knife-blade-master-switch-12v-24v-battery-disconnect store_origin: GB region: United Kingdom --- # 750A max current Vertical & adjustable install Brass corrosion-resistant build Top Post Knife Blade Master Switch 12V 24V Battery Disconnect Cut Off Shut Off for Auto Car RV-Marine Boat Truck Vehicle (Negative,Vertical) **Brand:** cozyehoo **Price:** £17.69 **Availability:** ✅ In Stock ## Summary > 🔋 Cut the power, not your freedom – master your battery with ease! ## Quick Answers - **What is this?** Top Post Knife Blade Master Switch 12V 24V Battery Disconnect Cut Off Shut Off for Auto Car RV-Marine Boat Truck Vehicle (Negative,Vertical) by cozyehoo - **How much does it cost?** £17.69 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.co.uk](https://www.desertcart.co.uk/products/225216885-top-post-knife-blade-master-switch-12v-24v-battery-disconnect) ## Best For - cozyehoo enthusiasts ## Why This Product - Trusted cozyehoo brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Built to Last:** Premium brass construction ensures superior corrosion resistance and conductivity - • **Energy Saver Mode:** Eliminates battery drain by fully disconnecting power when not in use - • **Powerhouse Protection:** Handles up to 750A max current for heavy-duty vehicles and marine use - • **Effortless Installation:** Adjustable vertical knife switch design for quick, hassle-free setup - • **Universal Compatibility:** Works seamlessly with 6V, 12V, and 24V top post negative battery terminals ## Overview The Top Post Knife Blade Master Switch is a heavy-duty, brass-made battery disconnect switch designed for negative top post terminals. Supporting up to 750A max current and compatible with 6V, 12V, and 24V systems, it offers easy vertical installation and effectively prevents battery drain and unauthorized use across cars, trucks, RVs, boats, and more. ## Description Product description COZYEHOO Top Post Knife Blade Master Switch, Used for preventing battery drain on car that are not driven often the product is compatible with cars Rv trucks vehicles boats and tractors etc. used the product to prevent battery drain,prevents battery drain during long periods of inactivity, especially on older vehicles with electrical system issues. heavy-duty switch, made of brass material, corrosion resistance, conductive performance is good, durably made for safety use Material: Brass, PVC Maximum Current: 750A Rated Current: 250A Package Included: 1x Battery Disconnect Switch Installation Firstly, disconnect the battery cables from the battery, always disconnect the negative cable first followed by the positive cable. Attach the battery disconnect to the negative battery terminal and tighten but do not over tighten. With the lever on the switch continuously open, connect the negative battery cable you removed from the battery to the opposite end of the disconnect switch. Make sure you have a good connection. Note 1.Mount on negative battery post，Never connect the battery disconnect switch to the positive terminal of your battery. It is usually won’t fit and dangerous. 2.Lead acid batteries are corrosive and explosive, remove any jewelry and always wear safety grasses gloves when working around the lead acid battery. 3.If your plan on the leaving your car for a long time without charging in this is a good way to do it. You don’t need a trickle charger its also a good secondary theft deterrent. You can kill the battery that way the car won’t start. 4.there are 3 kind of battery pole on the market,our switch only fit for 0.59-0.67IN(15-17mm)standard battery top post negative,please measure your battery pole before purchase. Review: Works on my pickup truck - 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. Review: Works great - Installed on my car and it works great. Easy to install ## Features - 【COMPATIABLE】This knife-blade battery disconnect switch is suitable for TOP 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 top post battery disconnect switch is made of brass material, corrosion resistance, conductive performance is good, durably made for safety use - 【EASY TO INSTALL】This battery doctor knife switch for top post batteries can be adjusted into a vertical knife switch through the bottom of the screw, easy to install & simple to use. Switch the knife, then power will cut - 【SAVE ELECTRYCITY】This 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. ## Product Details - **Operation Mode:** Off - **Current Rating:** 250 Amps - **Operating Voltage:** 12 Volts - **Connector Type:** Screw - **Brand:** COZYEHOO - **Item dimensions L x W x H:** 3.7 x 2.64 x 0.8 inches - **Circuit Type:** 1-way - **Mounting Type:** Surface Mount - **Actuator Type:** Rotary - **Contact Material:** Brass ## Images ![Top Post Knife Blade Master Switch 12V 24V Battery Disconnect Cut Off Shut Off for Auto Car RV-Marine Boat Truck Vehicle (Negative,Vertical) - Image 1](https://m.media-amazon.com/images/I/61-BT1v4vcL.jpg) ![Top Post Knife Blade Master Switch 12V 24V Battery Disconnect Cut Off Shut Off for Auto Car RV-Marine Boat Truck Vehicle (Negative,Vertical) - Image 2](https://m.media-amazon.com/images/I/618-BB7tFkL.jpg) ![Top Post Knife Blade Master Switch 12V 24V Battery Disconnect Cut Off Shut Off for Auto Car RV-Marine Boat Truck Vehicle (Negative,Vertical) - Image 3](https://m.media-amazon.com/images/I/610-iRq9V7L.jpg) ![Top Post Knife Blade Master Switch 12V 24V Battery Disconnect Cut Off Shut Off for Auto Car RV-Marine Boat Truck Vehicle (Negative,Vertical) - Image 4](https://m.media-amazon.com/images/I/61f42RPliLL.jpg) ![Top Post Knife Blade Master Switch 12V 24V Battery Disconnect Cut Off Shut Off for Auto Car RV-Marine Boat Truck Vehicle (Negative,Vertical) - Image 5](https://m.media-amazon.com/images/I/619lVwf0fdL.jpg) ## Available Options This product comes in different **Style** options. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Works on my pickup truck *by T***A on March 11, 2026* 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. ### ⭐⭐⭐⭐⭐ Works great *by R***. on April 3, 2026* Installed on my car and it works great. Easy to install ### ⭐⭐⭐⭐⭐ Quality *by R***Y on April 21, 2026* High quality great value ## Frequently Bought Together - Top Post Knife Blade Master Switch 12V 24V Battery Disconnect Cut Off Shut Off for Auto Car RV-Marine Boat Truck Vehicle (Negative,Vertical) - Side Post Knife Blade Master Switch, Ampper 12V / 24V Battery Disconnect Switch Isolator for Marine Car Boat RV ATV Vehicles (with Long Bolt) - Ampper Top Post Battery Disconnect Switch, 12-48 V Battery Power Cut Master Switch Disconnect Isolator for Car, Vehicle, RV and Boat (Negative, On/Off) --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.co.uk/products/225216885-top-post-knife-blade-master-switch-12v-24v-battery-disconnect](https://www.desertcart.co.uk/products/225216885-top-post-knife-blade-master-switch-12v-24v-battery-disconnect) --- *Product available on Desertcart United Kingdom* *Store origin: GB* *Last updated: 2026-05-31*