Thank you for viewing. This is a Yamaha 53HL (large shank) mouthpiece for euphonium and trombone. It is said to be the signature model of Shoichiro Oinuma, and is a phantom mouthpiece that was only included with the YEP842S for a short period of time in the past. Although the details are unknown, it is said to be the same as the YAMAHA SH SPECIAL, or to have been made based on the Black & Hill 4G. There are inevitably some insertion marks on the mouthpiece receiver, but it is in very clean condition overall, and has been cleaned and disinfected. There is no box for the mouthpiece itself, so it will be wrapped in air-cushioning material for shipping. Please note that due to my irregular work schedule, it may take some time to respond to your inquiries and ship the item. Thank you for your understanding.