Yamaha standard trombones were designed to make it easier for beginning students to sound good - and as soon as possible. They are produced in Yamaha workshops by highly trained craftspeople with very similar specifications and manufacturing processes as Yamaha use on their top-of-the-line models. And every single instrument is stringently test-played and inspected by an expert. This is why some top artists have commented that Yamaha standard models are very close to pro trombones in quality, yet are much easier for beginners to play. The standard models are durable, high quality trombones which offer a perfect entry into the world of music. The Yamaha YS154/CN Tenor Trombone Features: Key: Bb Bore: M 12.7mm (0.500) Bell: Yellow brass, 204.4mm (8) Weight: Standard Outer slide: Yellow brass Inner slide: Nickel silver Finish: Gold lacquer