Extended Bung; 1 in.; Mild Steel by Innovate Motorsports. For the last couple of years you may have noticed that all Innovate Motorsports wideband kits contain a 1" weld-in bung instead of the standard 1/2" bung. The 1" bung will allow the sensor to sit flush with the exhaust just inside the bung therefore eliminating restriction, O2 contamination (from leaded fuel & rich conditions). By doing this will help you in extending the sensors life. Exhaust gas sampling and accuracy is not affected in any way. We highly recommend the use of the 1" bung for high horsepower and leaded fuel applications. We still carry the 1/2 Bung & Plug kit for those who prefer them.