TheEnve Twin Bolt Seatpost Hardware Kit isSuitable for ENVE carbon seatposts with a two-bolt clamp design, This kit contains a complete clamp assembly including two cradles for standard and oversized saddle rails. Enve Twin Bolt Seatpost Hardware Kit Features complete clamp assembly For Carbon Seatposts with two-bolt clamp design PLEASE NOTE Not suitable for first generation (pre-2015) designs with a single bolt clamp.