The series of mouthpieces with “cup type R” are lead mouthpieces. A small number of models are available which differ from each other in terms of their nominal diameter. The proportional ratios of all parameters are retained in the nominal diameter variants. These mouthpieces have a very small cup depth and a small bore as well as an extended cylindrical bore. The balanced cup geometry offers a very quick and direct response. This mouthpiece was developed with special attention to the cup geometry in coordination with the backbore and is characterized by an excellent sound projection for lead trombone.