Picket Brass KO#4 KO Model, Large Bore, Silver Plated Finish Retail Price: ¥52,800 This is a model designed in collaboration with Koichiro Yamamoto, principal trombone player of the Seattle Symphony Orchestra. It has excellent response and a powerful tone, making it a popular mouthpiece. It's also popular with euphonium players. It was used for about 2 months, approximately 2 hours a week. There are some scratches on the shank from insertion and removal. The original box is not included, but it will be carefully packaged to prevent damage during shipping. As you can see, the current retail price is quite high, so I hope it will be useful for someone who needs it.