Yamaha 400 Series Trombones feature a beautiful rich tone, balanced response and perfect mechanics. They are easy to play and "Pro" models in virtually every way - except their prices. Their bore and bell sizes are the same as the sizes of professional models, and they boast a hand-crafted assembly which you would normally expect only for a top-of-the-line trombone. All models feature 8-1/2" bells made of top-grade gold brass for a warm, rich sound which can fill a concert hall, and offer incredibly accurate intonation and smooth quick slide action. They also deliver a quick response and comfortable playability which is consistent in almost any register, at almost any dynamic. The YSL-446GE and features Yamahas original wrap for the F-attachment, which is characterized by a surprisingly open, free-blowing response, and by remarkably smooth valve action.