Inner Diameter: .630 measured .04 inches into the cup.
Outer Diameter: 1.094
This mouthpiece has an extra-shallow V cup which has a cup volume similar to a Wedge S cup, but it is divided between an extra shallow upper cup and deeper V shaped lower cup. It resembles a Parduba, Callet Superchops, and other modified V shaped shallow cups. The result is more secure slotting in the upper register and a more open blow. The Lead V cup with a #27 throat feels much like an S cup with a #25 throat. It is an excellent mouthpiece for commercial lead and also for pit and pops. This is also a good mouthpiece for Piccolo trumpet if one prefers a shallow cup.
Backbore: This top is best used on an S (Small) backbore which can be purchased here.