Built for use with ratchets and breakers bars, the TEKTON 47749 Offset Oxygen Sensor Socket makes removing and installing oxygen sensors on vehicles with computer-controlled engines easy. A heat treated, chrome molybdenum steel construction ensures that the socket will take on oxygen sensors time and time again. The corrosion-resistant black phosphate finish also adds longevity to the socket. Designed with mechanics in mind, this socket works quickly and efficiently in the tight space around oxygen sensors. The 6-point beveled nose design securely grips sensor fasteners, preventing damage to the sensor. A wire gate allows you to easily slip the socket onto the sensor, preventing damage to the wires. And with the offset design, it's possible to access the oxygen sensor from the side, not the top, which eliminates the possibility of damage to wires. Even in low light, the high-contrast, permanent, laser etched size markings are easy-to-read. The size is also engraved into the chrome molybdenum steel on the top of the socket.