Denis Wick SM4 Large Shank Gold-plated Euphonium Mouthpiece (also compatible with Trombone) Please be aware that there is some wear and tear on the plating of the rim and throat due to age. Please only purchase if you understand this. For size comparisons with other brands, please refer to pages 11-12 of the following website: https://www.shimokura-wind.com/img/accessory/brass_wind_mp.pdf #mouthpiece #euphonium #trombone #brassband #windband #brassinstrument