Crupi Rear Hub Lock Ring and Spacer Kit Description: The Crupi Rear Hub Lock Ring and Spacer Kit consists of a Shimano compatible lock ring and a full set of spacers to get that cog mounted onto a Crupi hub. Features: Includes a Shimano compatible lock ring (Park F-R5 Lock ring Tool needed for installation) Includes the following spacers: 0.5mm (1), 1mm (1), 2mm (1), 3mm (1)