The Santa Cruz Reserve 27 I9 Boost MS/CL 29" Carbon Wheelset is made from carbon fiber and features DT Swiss 350 Boost Hubs, XD Driver Bodies with Standard Front End Caps. A little Santa Cruz video on a bike web site debunked every skeptic's fear about the long-term durability of carbon fiber bicycle frames. Now Santa Cruz is doing the same for wheels with the Reserve. Their confidence in the design and strength of their wheels is backed up by a lifetime warranty, just like Santa Cruz frames. Everything from the thickness of the rim beads to the external spoke hole reinforcements comes purely from the experience of knowing what riders need at every level -- from international racing to your local trails. Santa Cruz takes great pains to use readily-available, standard parts on their rims. Featuring J-bend spokes, mechanical-lock nipples (that you can access without taking the tire and rim strip off), and hubs from DT Swiss, Industry Nine make building good wheels easier and maintaining the wheels or finding spares a lot easier too. The Santa Cruz Reserve 27 I9 Boost MS/CL 29" Carbon Wheelset is the strongest on the market.