Electronic Specialties 191 Relay Buddy Pro Test Kit Kit includes Relay Buddy tester, 5 new relay adapters and blow mold case Relay Buddy is a quick go/no go tester for the most common automotive relays With the included adapters, Relay Buddy now tests 5 different relay types and also tests shielded relays Relay Buddy will fail the relay and light the red LED if any of the test cycle proves unsuccessful during the test session; green light if relay is good Settable to 4 and 5-pin relay and uses vehicle's 12 volts battery for power