Paul Components Chain Keeper 31.8mm BlackMachined aluminum Chain Keeper works either as a Singlespeed guide or with a 1X multi speed set up Clamp version mounts to the seat tube in place of the front derailleur and comes in 3 sizes Wide mouthed chain block and adjustable rod allow for precise alignment Use chain keeper extension (PC 2909) to fit some difficult frames (full suspension, tapered seat tube) Not intended for DH, FR, or big hit use Made in USA TECH SPECS model chain keeper mount