SKU: 47674048636

Blue Sea 300A Red Mini m-Series On/Off Battery Switch w/ Lockable Key

Sale price$51.54 Regular price$57.27
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Ships within 48 hours · Estimated delivery Sep 23 - Sep 28

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Description

Blue Sea 300A Red Mini m-Series On/Off Battery Switch w/ Lockable KeySecure High Current Switching for Marine and Vehicle Systems The Blue Sea m Series Battery Switch sets the standard for compact, high performance power isolation. Designed for marine, caravan, and RV applications, this switch manages a single battery bank, allowing users to safely disconnect power during maintenance or storage. With a continuous rating of 300 Amps, it is perfectly sized for outboards, small petrol engines, and diesel engines,

Secure High-Current Switching for Marine and Vehicle Systems

The Blue Sea m-Series Battery Switch sets the standard for compact, high-performance power isolation. Designed for marine, caravan, and RV applications, this switch manages a single battery bank, allowing users to safely disconnect power during maintenance or storage. With a continuous rating of 300 Amps, it is perfectly sized for outboards, small petrol engines, and diesel engines, providing robust power handling without the bulk of industrial-grade switches.

Integrating a battery switch is essential for preserving battery life. By turning the switch to the 'Off' position, you eliminate parasitic loads that slowly drain batteries over time. This ensures that when you return to your boat or vehicle, your power system is ready to go. Its compact form factor allows for installation in tight spaces where traditional heavy-duty switches cannot fit.

Lockable Security for Safety and Theft Prevention

A standout feature of this specific model is the lockable key mechanism. Unlike standard rotary switches, this unit includes a removable key that secures the switch in the 'Off' position. This functionality provides two critical benefits: enhanced security and maintenance safety.

For vessel or vehicle owners, the key acts as a theft deterrent, preventing unauthorised use of the engine or electrical system. For technicians and DIY enthusiasts, it serves as a safety lockout, ensuring the circuit cannot be accidentally energised while working on the electrical system. This reduces the risk of short circuits and electrical shock during repairs.

Engineered for Harsh Environments

Reliability in marine environments requires superior materials. The m-Series uses tin-plated copper studs to offer maximum conductivity while resisting corrosion caused by salt mist and humidity. The studs feature a one-piece design, which is a significant improvement over standard two-piece bolts. This design ensures the stud never loosens from the switch body over time, maintaining a solid electrical connection and reducing the risk of overheating—a common point of failure in generic switches.

The unit is housed in a reinforced casing with an isolating cover that protects the rear contacts from accidental shorting. Breakout tabs on the cover allow for wire access in any direction, simplifying the wiring process in complex setups.

Versatile Connection Options

The switch is designed to accommodate modern heavy-duty cabling. The 3/8" (Approx. M10) stud terminals are robust enough to accept heavy-duty lugs, ensuring secure, low-resistance connections. With a stud length of 7/8" (22 mm), the terminals can accept multiple cable lugs, allowing for easy integration of additional loads or charging sources directly at the switch.

  • 300 Amps continuous rating handles substantial 12V, 24V, and 48V loads comfortably.
  • Lockable key design prevents accidental activation and enhances security.
  • Tin-plated copper studs ensure maximum corrosion resistance and electrical flow.
  • One-piece terminal studs prevent loosening, reducing fire risks and connection failures.
  • Flexible mounting with breakout tabs supports various cable entry angles.
  • Ignition protected marking makes it safe for installation aboard petrol-powered boats.

Improve System Safety Today

Upgrade your battery management system with the Blue Sea m-Series Lockable Switch. Whether you need to secure a vehicle against theft or ensure safe isolation for maintenance, this switch delivers professional-grade performance in a compact package.

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 47674048636

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4.1 ★★★★★
Based on 27 reviews
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Product Reviews
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Verified Purchase
Gabrila
Phoenix, US
★★★★★ 5
Highly Recommend – Amazing Results on My Honda Accords!
Size: 1 Count (Pack of 1), Size: 1 Count (Pack of 1)
I recently used the Cerakote Headlight Restoration Kit on both my 2008 and 2014 Honda Accords, and I’m genuinely impressed. The headlights on both cars were badly oxidized, hazy, and yellowed from years of sun exposure. After following the kit’s instructions, they look crystal clear and almost like new again. The process is pretty straightforward and beginner-friendly. It does take roughly an hour per headlight set if you follow all the steps carefully and allow proper air drying time before the final clear coat. There’s a bit of elbow grease involved with the sanding and polishing stages, but nothing overly difficult. The kit provides everything you need, and the instructions are clear. The results are excellent! Both cars now have headlights that look factory-fresh. I’m really happy with how bright and clear they are at night. Best part? I saved a ton of money by restoring them instead of buying expensive OEM replacements. The only minor uncertainty is long-term durability (how well the clear coat holds up after a couple years of sun, weather, and car washes), but for the price and the dramatic improvement I saw, it’s absolutely worth it. I’d definitely buy this kit again if needed. Highly recommended for anyone dealing with cloudy headlights. Great product that delivers professional-looking results at a fraction of the cost!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 3, 2026
C
Verified Purchase
Cleaver
West Palm Beach, US
★★★★★ 4
Best product I've tried so far but still temporary. YMMV.
Size: 1 Count (Pack of 1)
This product really does work. It is the best I've used. I purchased in September 2024 and am writing this review in May of 2026, roughly one year and 8 months later. I noticed product failure a little after a year after application and it has been degrading slowly since. Currently the product is visible like a layer of clear paint flaking off and you can physically scratch some off. Here are the pros and cons. Pros: Clarity, relative ease of use, value Cons: Taping and sanding, doesn't last for as long as you own your car as claimed Best used as a temporary fix. Bottom line, would I use it again? Yes. What am I doing today? Replacing the headlights completely. Why? I plan on keeping my car for longer than a year.
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Reviewed in the United States on May 8, 2026
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Verified Purchase
Sahiti
Belleville, US
★★★★★ 5
Review After Using on 3 Different Cars over 3 years
Size: 1 Count (Pack of 1)
Cerakote Headlight Restoration Kit : After Using on 3 Different Cars over 3 years This is my second time purchasing the Cerakote Headlight Restoration Kit, and I’ve now used it across three different vehicles. At this point, I feel comfortable saying this product genuinely works when used correctly. Before trying this kit, I considered replacing my headlights entirely. The cheapest replacement set I found was around $150 just for the parts. Installation would have required removing the grille, bumper, and other components, which adds time and complexity. For an older vehicle, that didn’t make financial sense. Instead, I chose to restore the original headlights. Cost and Value My first package cost me $17, and I restored two cars with that single kit ( about 9$ per pair). That alone made it worth it. For under $20: I restored two separate vehicles Avoided buying new headlight assemblies Avoided removing the bumper and grille Compared to a $150+ replacement plus labor, the savings are significant. Durability 1 year+ under direct Cali sunlight (currently on year 2 and still good) First Car – Learning the Process The first time I used the kit, my results were decent but not perfect. That was mainly because I didn’t fully understand how sanding and polishing actually work. ( this reoxidized fastest under 8 months, but it was mostly my fault) I didn’t initially realize: The headlight needs to stay wet during sanding Oxidation must be completely removed before applying clear coat Even pressure matters/ 50% overlap coverage when appling ceramic Once I understood that sanding is the most important step, everything improved. Second Car (beater) Major Improvement The second vehicle was heavily oxidized and yellowed. I used the remaining material from that same $17 kit and restored it completely. The clarity difference was dramatic. It looked close to factory condition, and night visibility noticeably improved. That was when I realized the product itself is solid; the key is proper technique. Third Car ; Recent purchase By the third car, the process felt straightforward. I followed the instructions carefully, kept the surface wet while sanding, and applied the clear coat evenly in one smooth pass. The final result was clear, glossy, and uniform. No haze, no streaking. Durability On my first vehicle, the restoration lasted close to a year perfectly( I sold that car this year and it still had clear headlights), and that car was parked outside in direct sun most days. For a DIY kit at this price point, that level of durability is impressive. Final Thoughts I seriously considered spending $150 on replacement headlights( this was cheapest ) and dealing with removing body panels. Instead, I spent $17 and restored two cars. Now having used it on three vehicles, I can say this kit is effective, cost-efficient, and worth the time if you follow the process properly. It does require effort and patience, but the results justify it. I would purchase it again.
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Reviewed in the United States on February 18, 2026
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Verified Purchase
YetAnotherITGuy
Chelsea, US
★★★★★ 5
works as advertised!
Size: 1 Count (Pack of 1)
I purchased this kit to renew the headlights on my 2016 Nissan Frontier pick-up. The headlights had become slightly oxidized and dull -- not that bad but it was bothering me and for the price of the kit I figured it was worth the effort to attempt to renew them. All I can say is -- WOW, what a difference. The end result looked like new -- clean, brilliant and bright. Read the directions (2 or 3 times) and follow them EXACTLY. Total time for me from opening the kit to being done was about 2 hours and I was taking my time. This kit is different in that the final step applies a UV resistant coating which really makes the glass super transparent. Great investment in the time and money. I can't stop admiring my new (old) headlights!
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Reviewed in the United States on May 14, 2026
A
Verified Purchase
Alex
Boise, US
★★★★★ 5
Incredible Results! The "Z-Line" is Back!
Size: 1 Count (Pack of 1), Size: 1 Count (Pack of 1)
I’ve tried a few "wipe-on" fixes in the past, but the CERAKOTE® Ceramic Headlight Restoration Kit is in a completely different league. If you are tired of hazy, yellowed lenses and weak nighttime visibility, look no further. 📖 Instructions & Ease of Use The first thing that stood out was the clarity of the instructions. The kit breaks everything down into a simple, step-by-step process. Even if you aren't a "car person," the directions are foolproof. They don't just tell you what to do; they explain why each step matters, which gave me the confidence to get the job done right the first time. ✨ Restoration Effectiveness As you can see in my Before and After photos, the transformation is night and day. My headlights went from a dull, oxidized yellow to a factory-fresh, crystal-clear finish. It didn't just "clean" them—it completely rejuvenated the plastic. 🔦 The Real Test: Light Output & Beam Pattern The most impressive part isn't just how the car looks, but how it performs at night. I’ve included a photo of my car parked against a wall in the dark to show the comparison: Passenger Side (Restored): You can see a sharp, distinct cutoff line and the perfect "Z-line" pattern. The light is focused exactly where it needs to be on the road. Driver Side (Not Restored yet): The light is completely distorted. There is no cutoff, just a messy blob of light that scatters everywhere, likely blinding oncoming traffic while providing less actual visibility for me. Final Verdict This kit doesn't just make your car look better; it’s a genuine safety upgrade. Seeing that crisp Z-line back on the wall proves that the clarity is internal as well as external. Highly recommended!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 15, 2026

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