Quiets derailleur and chain contact compression moulded 5mm25mm neoprene on xc oriented designs 5mm neoprene on dh and freeride 35mm on 05 enduro abrasion resistant outer covering with stitched edges for durability rubber printing on the inside surface keeps the sleeve in place derailleur housing stop cut outs for a precise fit custom fit gives a more integrated look while protecting the frame black