Perantucci PT-48 Tuba Mouthpiece - 33.5mm cup diameter, deep funnel-shaped cup (rounded at bottom), 8.0mm rim, rounded inner and outer edges, 8.5mm bore, similar to the PT-44 yet larger, dark sound with a pronounced core, excellent for medium-large and large-bore C and Bb tubas, recommended for those who find the PT-50 and PT-88 too big.