BoltSizeIt Electrical Terminal Gauge
(Wire, Cable & Lug Sizer)

$8.99

When you open a panel you didn't wire, guessing isn't an option. For service technicians and inspectors, identifying existing wire gauges and lug sizes is critical for safe retrofits and repairs. The BoltSizeIt Electrical Terminal Gauge is the diagnostic standard for maintenance crews who need to verify "what’s there" before they can fix it.
Verify Existing Circuits Instantly This template acts as a comprehensive diagnostic tool for troubleshooting unknown wiring and battery systems. It eliminates the guesswork when documenting existing panels or replacing corroded ends:
Wire Verification Accurately identifies wire diameter from 22 AWG (control wiring) up to 250 MCM (service entrance/industrial).
Lug & Post Sizing Gauges battery lugs, starter lugs, and posts from #8 to 4/0, ensuring replacement parts match the original specs.
Dual Rulers Features integrated 7-inch and 180mm rulers for measuring strip lengths and clearances.
Diagnostic Range Covers the most common sizes found in automotive and industrial troubleshooting.
Service-Ready Durability Maintenance work is often greasy work. Whether you are troubleshooting a generator, servicing a fleet vehicle, or inspecting a marine bilge, this gauge is built to survive. It is molded from high-quality, impact-resistant plastic that is chemically treated to resist battery acid, water, alcohol, oil, and grease.

Built to Last

Size Range Lugs and Posts from No. 8 to 4/0 & Copper wire diameter from 22 ga. to 250 MCM
Material Specially formulated, non-conductive, polymer designed to resist water, oil, grease, alcohol and just about anything else you can throw at it.
Non-Conductive Material Lightweight plastic construction adds a layer of safety near live circuits.
Portability Flat design fits easily in a diagnostic bag, clipboard, or glove box.

Complete Your Toolkit

You have identified the wire, but what about the terminal screws? Service panels and relays are filled with small standard machine screws that often need replacement. Ensure you have the right tool to measure those fasteners too:

SPECIAL WHOLESALE PRICING AVAILABLE

Just like our other bolt gauge tool products,
special pricing is available for wholesale orders.

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