The X-Lab carbon wing is an extremely functional, well-designed rear hydration system capable of carrying CO2 cartridges, an inflator, one or two bottle cages, tires, tubes and other items so they are very accessible. It is designed to clamp to standard 7mm saddle rails. The lightweight high modulus carbon carrier only weighs 55 grams. One of the key features is the dual mounting holes for the saddle rail clamps. One position sets the bottle cages close to vertical and the other inclines the cages.