Near-Universal Relay Tester Kit: This automotive circuit tester comes with 6 popular auto relays and one universal relay tester lead, making it useful for a broad range of makes and models Easy Operation: Simply choose the applicable dummy testing relay, plug it into the fused relay block, connect car relay tester to vehicle's battery, and power on for circuit health reading Total Electrical Troubleshooting: Tool can test an entire circuit from the battery to the component; Bypass relays for pressure testing, distributor or cam shaft adjustments, A/C filling and more Efficient and Effective: These electronic test equipment kits allow you to identify at the push of a button if a wire, a part, or a relay is defective; Cut relay related diagnosis time by 75% Convenient Carrying Case: Everything you need for professional automotive diagnostics stays organized in one compact case; It's easy to keep your diagnostic test tools organized and ready to go