It is extremely durable and weather resistant, and the bell front design enhances tonal projection. The intonation is highly accurate and players will appreciate the securely centered notes and easy playability. Features Hand-lapped valves and slides Hand-lapping is a time-consuming finishing process which results in an airtight valve/piston fit for noiseless, responsive action. Well-balanced The YSH-301WB is well-balanced so it is easy to hold while marching. Heavy bracing throughout Because the sousaphone is used in marching band, it has heavy bracing throughout the instrument to make it more durable at the vulnerable points. Pressure formed tubing Perfectly rounded tubing results in less turbulence and a smoother air flow, thus allowing for an excellent scale and reduced resistance. Fiber-reinforced plastic The material in the YSH-301WB makes it lightweight to reduce fatigue while marching. The ABS resin bell is durable yet lightweight. Specifications Level: Sousaphone Key of: BBb Size: 4/4 Bore: 0.728" Bell Diameter: 26 1/8" front facing bell Leadpipe Material: Yellow Brass Body/ Bell Material: Fiberglass reinforced plastic; ABS resin bell Finish: Clear epoxy lacquer (slides, valve casing, and leadpipe) Mouthpiece: 67C4 Pistons/ Valves: (3) Nickel-plated, front action Case: SH-43 Options / Included: SH-31 soft case (YSH-301B); With case (YSH-301WC)