Warburton FT. LAUD 7D GP trumpet mouthpiece. This is a top from the FT. LAUD era, made with the original tools before the factory burned down. Nominal values (size 7) Inner diameter: 16.00mm (0.630 inch) Outer diameter: 26.80mm (1.055 inch) Drill size: #27 I have many other items for sale, so please check them out if you'd like. #TPY's list of items for sale Type...Trumpet Accessories/Parts...Mouthpiece