Description

NAMZ, 18mm to 12mm exhaust sensor bung reducer set

Used in custom applications to reduce exhaust sensor thread from 18mm x 1.50 to 12mm x 1.25 so late H-D models, equipped with 12mm O2 sensors, can be used with earlier 18mm sensor style exhaust systems. Note: For 10-16 Touring models an extra extension cable is required, which is available as 578303 bung set & cable extension kit.

Fits: > 12-17 Softail, Dyna (with pre-2012 exhaust) (NU); Custom applications to reduce 18mm O2 sensor holes to 12mm