MPN: Electronics Specialties 306B, ESI 306B, or ESI306B. Electronic Specialties 306B - Fuse Buddy Test for ATC Car Fuses 0 to 30 AMP. ESI 306B - 0 - 30 AMP ATC Blade Car Fuse Circuit Tester. Very easy connection into ATC Blade fuse socket, the end of the tester is shaped just like a fuse.
