The OEMTOOLS Oxygen Sensor Socket Set, No. 37110, services hex vacuum switches and oxygen sensors. The set includes three sockets sizes for most applications: 3/8" Drive 7/8" Deep, 3/8" Drive 7/8" Crowfoot, and 1/2" Drive 7/8" Deep Crowfoot. It comes in a blow molded cast and has chrome fitting and black oxide finish for easy cleanup.