Need to move an O2 sensor or add a new one? You need an O2 bung!
Available in two styles. The no-weld version is attached to a strap that goes around the exhaust. It fits 2.25" and 2.5" piping. The weld version has to be welded into place and can be used on any size pipe. A hole will have to be drilled in the pipe in both cases.
Note that stock exhaust systems - including the ND parts - are usually smaller than 2.25" OD, so the no-weld version will not work in this case.
Some aftermarket exhausts, including most of ours, include extra O2 bungs already, so check to make sure you need one before you order.