Thumb B(flat) Roller
A roller for the thumb B(flat) should be paired with either a roller or a crown on the pancake key. The position of the thumb makes movement from a plain pancake key to a roller B(flat) difficult.
Catalog Number: 69
Available On: 601, 660, 201, II, III, & IV
Standard Included On: 101, I, 240 & 220