SFS30.W17-BOX - Sturmey Archer SFS30 single freewheel, 17T, for wide 1/2" x 1/8" chain. BSC 1.37 x 24 tpi, chrome plated. - 4710944239546

SFS30.N18-BOX - Sturmey Archer SFS30 single freewheel, 18T, for narrow 1/2" x 3/32" chain. BSC 1.37 x 24 tpi, chrome plated. - 4710944239621

SFS30.W18-BOX - Sturmey Archer SFS30 single freewheel, 18T, for singlespeed bikes. 1/2" x 1/8" chain size, BSC 1.37 x 24 tpi, chrome plated. - 4710944239553

SFS30.N20-BOX - Sturmey Archer SFS30 single 20T freewheel for narrow 1/2" x 3/32" chain, BSC 1.37 x 24 tpi, chrome plated. - 4710944239645

SFS30.W20-BOX - Sturmey Archer SFS30 single freewheel with 20T sprocket, for singlespeed bikes and 1/2" x 1/8" chains. - 4710944239577

SFS30.W21-BOX - Sturmey Archer SFS30 single 21T freewheel, 1/2" x 1/8" for wide chain, BSC 1.37 x 24 tpi, chrome plated. - 4710944239584

- 19T singlespeed sprocket for 1/2" x 1/8" chain. -