Features Key of BBb.728" bore26" yellow brass bellNickel plated valvesOptional case with wheels available Description Product Description The Yamaha YSH411 Sousaphone is possibly the best sousaphone around today. Yamaha has done extensive research in developing an improved marching low brass instrument. Upon examination you will find many of the same features on their top line marching equipment that you will on their professional solo and symphonic instruments. These instruments are "best in class".The full brass sousaphone for those who prefer the better sound quality of a brass instrument and don't worry about the weight of the equipment as much. This is a powerful sousaphone that will hold the sound together at all volumes.