Set of four relay test adapters make testing relays or live circuits quick and easy. Fit the most popular size relays on domestic and import vehicles. Simply remove relay to be tested, insert correct adapter and insert relay into adapter. No need to pierce wires or connect multiple jumper wires. Adapters have tabs for clamping and flat pads to place test leads on When using green four pin adapter be careful to align pins on adapter and relay correctly. Set comes in blow-molded case for storage.