The Yamaha GP 14C4 trumpet mouthpieces of the GP series are characterized by a centered and full sound. The gold-plated cup and rim are warm and comfortable on the lips. The additional Gewicht of it mouthpiece makes the notes hit the center better and the sound becomes fuller. The center cup provides a full sound that is at home in almost all musical genres. The GP 14C4 has an inner diameter of 16.88mm and a bore of 3.65mm.