Bb Valve Trombone in 2 lengths in clear lacquer
Brass, nickel silver ttrim, three monel piston valves, bore is .472 in./12 mm., bell is 8.070 in./205 mm
164 411 Model 560- short construction, 35.827 in./910 mm in length
164 511 Model 580- long construction, 43.70 in./1110 mm in length
Model 560 short pictured