ATA KDF-07A Single-Speed Bike Freewheel 18 Tooth Cog 1/2" x 1/8" New AB-21-V11

1/2 x 1/8" Single Speed Freewheel - BMX, Kids Bike etc. 18 teeth sprocket. Easy Suntour Type 4-Notch Tool Fitting. Threaded Type - Standard BSC 1.37 x 24 tpi.

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