"The Grail" Tuba MouthpiecesIn addition to our standard tuba mouthpiece models, we've finished development of "The Grail Series" models. These are reproductions of really great playing old Helleberg models that we have had an opportunity to examine and replicate. We have had great success with these models. The Grail Series Model I. D. O. D. Bore Cup TG1 1. 280 1. 830 Q (0. 332) XD TG2 1. 250 1. 890 P (0. 323) MD TG3 1. 250 1. 890 Q (0. 332) MD TG4 1. 260 1. 900 Q (0. 332) D