Miraphone Bass Trombone Model 691

Bb-Bass slide trombone, open wrap, quart-terz

Model: 691

Number of valves: 2

Style: open wrap quart-terz

Key: Bb/F/D/Gb

Bell diameter: 250 mm (9,843 inch)

Type of Body: Gold-brass Body

Type of Valve: CPU linkage nickel silver

Bore of inner slide: 14,3 mm (0,563 inch)

Material of inner slide: nickel silver-hard chrome

Material of outer slide: nickel silver

Material of mouthpipe: nickel silver

Mouthpiece: PO15

Finish: lacquered