3/8" 22MM Lambda Offset Oxygen Sensor Socket Wrench O2 Tool Kit Set Adapter Engine Wrench. Common 6 point, 7/8 in (22mm) socket, suitable for most oxygen sensors. It’s very handy. Even if you don't have a lot of experience working with cars, you can replace your O2 sensor with this tool to help with your car's emissions and gas mileage.
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