Michael Rath R3 Tenor, Bb Tenor Trombone, Bore: Ø 0.525"" (13.34 mm), Bell size: Ø 8"" (203.50 mm), Bell made of yellow brass, Outer slide made of nickel silver, Tuning slide made of yellow brass, Gooseneck made of yellow brass, Lead pipe: #31, Without mouthpiece and case