Brompton wheels & drivetrain specialist

This is the adapter for the 10T cog. 

Thread specifications:
Lower section: M30.5 x P1.0 (common cassette lock ring thread)
Upper section: M22 x P1.0

Please note that these adapters will not fit the standard 2 speed freehub, originally equipped on either the Brompton single/2 speed hub, or the Hubsmith rear hubs. The adapters are designed to work with the specific freehubs below. 

For Brompton 3 speed free hub (black color only)
For Hubsmith 3 speed free hub (black color only)