This is a beautiful unmarked Martin large chamber soprano mouthpiece, the preferred large chamber soprano mouthpiece for renown classical players ! It is in very good original condition and it plays superbly. I’ve had both marked and unmarked Martin pieces here before and this one is as good as any I’ve had. I played it with both # 3 Marca Superieure reeds and also with # 3 1/2 reeds. It was brighter with the lighter reeds and very textured and darker with the # 3 1/2. The audio sample is with # 3 1/2 reeds , played on my Selmer Serie III soprano.