A top post battery isolator for 12V systems that cuts electrical supply to stop battery drain and discourage unauthorised starting. Spurtar Top Post Battery Isolator Switch helps owners of cars, RVs and boats keep batteries healthy during long storage and between trips. Is this the simplest way to avoid an unexpected flat battery?
⚡ At a Glance
- • Current Handling: Handles 12V systems with 125A continuous and 500A momentary surge
- • Best for: Owners of cars, trucks, boats and RVs who need reliable storage protection
- • Not ideal for: Batteries without top-post 15-17 mm cone negative terminals or systems above 125A continuous
Top-post, knob-style disconnect made from solid brass for 12V applications up to 125A continuous. Installs on standard 15-17 mm negative battery posts and uses a green screw knob for manual connect and disconnect.
Protects battery life – thanks to manual top-post disconnect
Manual green knob tightens onto the 15-17 mm cone negative post to complete the circuit, and loosening the knob severs the connection. The switch cuts off parasitic draw by isolating the battery from vehicle electrical systems.
Less drain during months of storage, meaning fewer surprise failures and longer battery service intervals. Handy for seasonal vehicles and boats kept idle for extended periods.
Durable and corrosion resistant – with heavy duty solid brass construction
Solid brass body resists rust and corrosion, making the switch suitable for marine and roadside environments. Described as waterproof, the construction protects contacts from moisture that accelerates wear.
Reliable electrical contact and longevity even in damp or salty conditions, reducing the need for frequent replacements. Ideal where long-term exposure to the elements is likely.
Handles engine starting surges – with 500A momentary capacity and 125A continuous rating
Rated for 125A continuous current and able to cope with momentary surges up to 500A, the switch tolerates the high currents associated with starter motors. The knob design provides a secure mechanical connection under load.
Safe for normal vehicle starting cycles and accessory loads within the specified limits, giving confidence when disconnecting and reconnecting batteries. Suits a wide range of everyday automotive and marine applications.
✨ The 4 Key Reasons for Spurtar Top Post Battery Isolator Switch
- Solid brass construction – Prevents rust and withstands harsh marine and road conditions
- Waterproof design – Keeps terminals dry and reduces electrical faults during long storage
- Manual green knob – Easy on/off control, quick disconnect without tools for maintenance
- Top-post compatibility – Fits most 15-17 mm negative posts, simplifies installation on vehicles
📋 Technical Details at a Glance
- Category: Battery isolator switch
- Voltage: 12V
- Continuous current: 125A
- Momentary current: 500A
- Compatibility: Top post negative terminals, 15-17 mm cone
❓ Frequently Asked Questions
Q: Can the switch be used on any battery terminal?
A: Suitable for most top post negative terminals with a 15-17 mm cone, so check the battery post size before fitting.
Q: What current levels can the switch handle?
A: Rated for 12V applications with 125A continuous current and up to 500A momentary surge capacity.
Q: Is the switch resistant to corrosion and moisture?
A: Constructed from heavy duty solid brass and described as waterproof, offering protection against rust and corrosion.
🏆 Our Verdict
Suitable for vehicle and marine owners who want a simple, reliable way to prevent parasitic drain and unauthorised starting. Robust brass construction and clear current ratings make it a practical choice for routine storage protection and maintenance. Durable design and straightforward operation deliver long-term value for anyone needing dependable battery isolation.
