N20-24 Valve Lapping Blocks

Used for “lapping-in” newly replaced or repaired valves.
N20 Cornet/Trumpet, 5/8” (14.9mm)
N21 Small Baritone, 11/16” (17.5mm)
N22 Large Baritone, 3/4” (19mm)
N23 Small Bass, 15/16” (23.8mm)
N24 Large Bass, 1-1/16” (27mm)
N20-24 Set of 5 blocks listed above