The Cal-Van Tools 7-pc Oxygen Sensor Socket Set, No. 84200CV, is designed to provide an easy method to remove and install various sensors, sending unit, vacuum switches, and injectors on most domestic and import vehicles. Offset sockets are compromised of SAE and metric sized sockets, to be used with 3/8" or 1/2" drive ratchet and breaker bars. Some sockets come with a hex bottom to be used with a combination wrench.