Description Designed to adapt other mufflers to the Aussiespeed go kart coupler style header pipes, can be used with our coupler style Honda, Vanguard, Briggs & Stratton Animal, World Formula  or KX21 Subaru pipes. the 6 bolt steel flange has an outer diameter of 100mm with an internal diameter of 48mm with an overall length of 70mm The laser cut and punched flange has 2 spring retaining lugs that are pressed out of the steel flange then tig welded for extra strength. The steel flange has slotted bolt holes that can be bolted to mufflers with a mounting flange between 70mm to 90mm .