Shimano Alfine and Nexus Rear Hub Nuts Cog Snap Ring and Non-Turn Washers for Vertical Dropouts. Shimano Internally Geared Hub Small Parts Kits

Alfine hubs are packaged without small parts and require this kit plus a cog

Nexus hubs are packaged with small parts and cogs and do not require an additional small parts kit

Cassette joint does not fit Di2 Alfine hubs