Topeak MTX Beam Rack II Seatpost Mount Rack - A-Type Load Up and Roll Out The MTX Beam Rack II builds on the adaptive design of the popular original Beam Rack by crafting the beam arm to better suit the nuances of varying wheel and frame designs. The A-Type beam design makes an ideal fit for small and extra-small frames, giving riders a seatpost-mounted rack option even when frame geometry rules out a traditional rear rack. Features A-Type beam designmakes an ideal fit for small and extra-small frames MTX Quick Track(R) panelcompatible with MTX 1. 0 and 2. 0 system bags and baskets, and flips to adapt for bags from other brands Fits seatposts from 25. 4mm to 31. 8mmfor broad compatibility Integrated rubber bungee cordhelps secure loose cargo Rear light mountcompatible with a variety of light styles and sizes Carries up to 20 lbswith easy loading and quick-release seatpost clamp SPECIFICATIONSBeam Type A-Type (small frames)Seatpost Compatibility25. 4mm - 31. 8mm Max Load20 lbs Mount MTX Quick Track(R) panel | Topeak | Mtx Beamrack Ii Seatpost Mount Rack - A-Type Black | Rubber