This is the Bob Reeves trumpet mouthpiece, MS43S, supervised by Masashi Sugiyama, the Brass Educator. It's a mouthpiece with a standard 43 rim, a not-too-deep V-shaped cup, and a 22 throat, resulting in excellent breath support. It's designed to be well-balanced and easy to use with instruments like Bach Stradivarius and Yamaha Xeno. For those who found the MS model (with a slightly deeper V cup and a 20 throat) too demanding in terms of breath control, this model serves as a good "bridge." It shows some signs of use. Please check the photos.