I`ve been playing the trombone for three years, but I never really payed attention to the differnt kinds of tromebones that are around. So I was wondering what types I had. My first one I just got from Cascade music when I started out and all it says is Bach (serial # 082518). My other oner my parents got for free from a friend of theirs who didn`t play. It has Bundy H& A Selmer Inc. on it (s.# 156636). If anyone understands this stuff could the tell me plz.