Clutch Spring, for use on BSA models: Six spring clutches as fitted to BSA A,B and M Group models including : A7, A10 Swinging arm Pre-Unit twins (1954-59), M20,M21 Series (1949-58), B31,B32,B33,B34 (1949-60).
O.E.M: 66-3800
Length: 1-1/16"
Outer Diameter: 7/16",5/16
Supplied: Singles