Thank you for viewing. This is a JK 3EM horn mouthpiece. It was used for about six months. I am selling it because I switched instruments from an Alexander 103 to a Paxman and no longer use it. This mouthpiece has been tuned for wind instruments, so it resonates more than usual and feels better on the lips. It is easy to control, produces high notes easily, and I think it can produce a rich and dense sound. Also, the cup is slightly shallow, but due to the tuning, the tone is not much different from a 3DM. This is just my personal opinion. Specifications: Inner diameter: 17.5mm Cup shape: U cup Depth: Slightly shallow Bore size: 4.0mm Regular retail price: 15,400 yen (tax included) Purchase price: 10,285 yen (tax included) + Wind instrument tuning: 5,500 yen (tax included) Thank you for your consideration.