Designed specifically for circuit testing, Fuse Buddy plugs right into fuse socket - easy connection for circuit current testing. Fuse Buddy will measure circuit amperage from 0 to 20 Amps - time saving design. Unique design incorporates removed fuse to maintain circuit protection. Test range 0 to 20 Amps. .01 Amp resolution. Circuit testing made EASY! The Fuse Buddy Tester connects directly into the fuse socket, measuring from 0 to 20 Amps. No more clumsy connections at the fuse box, adapter fitting plugs directly into fuse socket and stays put. Removed fuse is plugged into the Fuse Buddy maintaining circuit protection. Great for diagnostic troubleshooting and parasitic drains.