This is a representative model from **Greg Black**, a brand highly trusted by trombone players. It's a premium brand with very limited domestic distribution, and is highly supported by professional musicians. The 5G is the most versatile model, often called the "go-to" choice. This particular item is a medium-weight specification, offering an excellent balance of weight and sound initiation, with characteristics of carrying sound and rich overtones. Bore: 25.8mm Cup Depth: Medium Deep Retail Price: ¥57,200 I am selling this as I switch to the New York series (5.75).