5-Speed internal geared coaster brake hub with gear ratio of 243% 25% gear steps Rotary gear selector without protrusions outside the frame Designed for heavy duty use A356 Aluminium hub shell Compatible with 16 to 22 teeth sprocket RR 5s Int 36H B/O 3/8 Alloy Sil 2400g CB 135mmUPC/EAN/GTIN: 4710944259407