APPLICATION The oxygen sensor socket set designed for the removal and installation of oxygen sensors, oil pressure switch, thermal sensor switch, and brake light switch on the vehicle. HIGH QUALITY Oil pressure sending unit master sensor socket is made of chromevanadium steel CRV for extra strength and longevity, finished with black oxide to avoid rust. SIZE Oxygen sensor socket kit includes 22mm 78, 27mm, and 29mm, fit with 38inch and 12inch ratchet drivers or extensions, the side cutout sections allow the sockets to fit over wiring harness and prevent damage to wires PACKAGE comes with a plastic carry case for easy storage, organization and carrying away. SERVICE 100 satisfaction guarantee, if there is any question, please feel free to let us know.