Fab-Pros plug for the O2 Bung with 18mm x 1.5 threads. Do not use other models with the allen wrench and risk the plug getting seized or stuck onto the bung where you'll have to break tools and strip parts trying to remove the plug.
Plug for O2 Sensor Bung M18 X 1.5 Threads - Male - 10-PACK with exped. shipping
Plug for O2 Sensor Bung M18 X 1.5 Threads - Male
Steel O2 Sensor Bungs and Plug Kit 02 SENSOR 18 X 1.5
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