They bolt on perfectly to a MDS 40/48, 40 & 46FX. TT PRO 46, etc.

You will need to readjust the needle valve.

These mufflers are bad about coming apart up in the air after you use them for a while. Early on, double nut the through rod. Eventually the through rod will pull out of the front piece. Then you will have to put a threaded rod all the way through it with double nuts front and rear.

Works better with smaller props that will let the engine turn up some rpm. (10-6, 11-6)

Jim