●Precision Double Bore The special double bore of 12.7 - 13.34 mm ensures a balanced and dynamic feel that helps young trombonists learn and refine their technique. ●DURABLE CONSTRUCTION The kids trombone features a durable nickel silver outer pull and hard chrome plated nickel silver inner pulls that ensure lasting durability and a smooth playing experience. ●Maximum playing comfort: individually adjustable hand support, ergonomically shaped valve lever and length-adjustable push rod with left/right thread guarantee fatigue-free and comfortable play. ●For the mobile musician: despite its technical features, the trombone weighs only approx. 1.6 kg and comes with a lightweight moulded case and practical backpack set for easy and safe transport. ●Box contents: Roy Benson childrens Bb/C trombone TT-220 - 8 inch brass baffle - 12.7 - 13.34 mm double bore - nickel silver outer cable - hard chrome-plated nickel silver inner cables - with ergonomic features.