Ducati 98 125 Bronco Exhaust Nut 0150-84-030

Ducati's part number for this nut is 0150-84-030, I believe.  It should fit just about all Ducati Bronco models, regardless of displacement.  ID is 34mm.

This beautiful nut is cast in BRASS, just like the originals, then chrome plated.  Unplated versions also available, for the vintage look you may want.