What type of wrench should I use on my O2 sensor

I have e30 m3. This is second time i have changed O2 sensor.I use a 7/8 wrench i cut in half.You can use either end open or box.Just use some muscle or small pry bar

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This post was auto-generated based upon a question asked on our tech article page here: Pelican Technical Article: Replacing your 3-Series E30 Oxygen (Lambda) Sensor

[Nick at Pelican Parts]

Also use a 6 point wrench and not a 12 point because it is easier to round off the sensor with a 12 point wrench.

- Nick