This is a professional tenor trombone made by C.G Conn in Elkhart, Indiana in about 1960. It has the classic dimensions that have been the archetype for many other trombones since: .500" bore hand slide, 8" bell. As played by Frank Rosolino and many others.
2-piece 8" brass bell, unsoldered rim
.500" bronze slide with chrome plated nickel inside tubes, nickel crook and trim
removable balance weight
minor loss of plating on inside slide tubes, but it's not noticeable with regards to slide action. The hand slide is outstanding
some evidence of dent removal from tuning slide crook