The Yamaha YSL-882GOR professional trombone has a medium large bore and an open wrap F attachment. It also has a gold brass bell making it slightly warmer sounding that the standard 882 model making it perfect for concert and symphonic musicians. One piece hand hammered bell A one-piece bell has an axial (lengthwise) seam, making it a continuous extension of the instrument's material. This results in pure, uniform resonance and superior tone. Larger bell The bell is 8 2/3" in diameter. The larger bell in combination with other design improvements, produces a singing, colorful open sound with a projecting solid core. Open wrap F attachment The open wrap has a more open feel and quicker response while using the F attachment. Narrow slide Having a narrow slide results in a faster slide technique allowing the player to get around the horn easier. Rounded Slide Crook Eliminating sharp turns in the crook will open the feel and response of the instrument. Adjustable Thumb Paddle The rotor paddle is adjustable for optimum comfort. Counter Balance Weight Adding a weight contributes to the trombones focused projecting sound. Mechanical Linkage Using a mechanical linkage on a rotor gives it strong, smooth operation. Slide lock The unique slide lock design on all Yamaha trombones keeps the slide locked in place and keeps it from accidentally falling. Pressure-formed tubing Perfectly rounded tubing results in less turbulence and smoother air flow. Newly designed case The new case is a compact contoured shape. Specifications Bore: .547" Bell: 8 2/3" Yellow Brass Bell Open Wrap with F-Attachment Reversed Tuning Slide Balanced Response Rotor Model: YSL882GOR