This is a vintage hard rubber Frank L Kaspar mouthpiece for the tenor sax. This piece dates back to Kaspar's Chicago days, not long after he purchased the Goldbeck company, and before he moved to Ann Arbor. The piece features a medium-large round chamber, and the original facing measures .074”. The mouthpiece is in phenomenal shape considering its age, with nothing more than fine surface scratching around its body and no significant wear to speak of. Plays with a dark tone.