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Battery Doctor knife switch with top terminal post

Battery Doctor

Battery Doctor PT-WIR20138 Knife Switch gps accessory

SKU CH-VK2N-0CY84 MPN PT-WIR20138

A knife switch that mounts on the negative battery post to isolate power and prevent unwanted drain or unauthorised use

  • TypeGPS Navigation Accessories
  • Features? Mounts on the negative post;? Disconnects batteries safely
  • Mounts on negative post for quick installation
  • Disconnects battery safely to prevent accidental drain
  • Stops unwanted battery drain during storage
  • Top post design suits low vertical operation
  • Model 20138 knife switch adds theft deterrent

Battery Doctor Knife Switch 20138

This top-terminal knife switch mounts directly on the negative battery post. It is designed for owners of stored vehicles, RVs and seasonal equipment who want a simple way to isolate the battery. The switch disconnects power quickly to prevent unauthorised use and unwanted drain. It suits anyone needing a straightforward mechanical cut-off for low, vertical installations.

Manual disconnect limits and safety

The switch provides a physical air gap only when the lever is thrown by hand. It carries no remote control, no electronic monitoring and no automatic reconnection feature. Users must reach the battery location each time they want to isolate or restore power. It cannot replace a relay-based system that requires timed or keyed operation.

Brass terminal construction and daily use

The 5/8 in. diameter top post accepts a standard battery cable clamp for a secure connection. Retail packaging protects the brass hardware during storage and transport. The low-profile vertical action keeps the handle clear of tight battery compartments. Regular inspection of the contact surfaces ensures reliable conductivity over time.

Highlights

  • Mounts on negative post for quick installation
  • Disconnects battery safely to prevent accidental drain
  • Stops unwanted battery drain during storage
  • Top post design suits low vertical operation
  • Model 20138 knife switch adds theft deterrent

Specifications

BrandBATTERY DOCTOR
TypeGPS Navigation Accessories
Features? Mounts on the negative post;? Disconnects batteries safely & easily;? Stops unwanted battery drain;? Retail packaging;? Top post; ideal for low, vertical operation;
Shipping weight0.95 kg
Package size182 × 117 × 64 mm

Questions about this item

Should I choose the PT-WIR20138 top-terminal switch or a side-terminal version?

The PT-WIR20138 is a top-terminal knife switch; choose it when your battery has vertical posts and you need low-profile vertical operation.

How does the knife switch stop unwanted battery drain once installed?

It mounts on the negative post and physically disconnects the battery, breaking the circuit so parasitic loads cannot draw power.

What cable clamp size does the 5/8 in. post accept in practice?

The 5/8 in. diameter post accepts a standard battery cable clamp for a secure connection.

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