Box Two Prime 9 Speed MTB Rear DerailleurClassed as Box’s most durable derailleur, this 9 speed rear mech offers super-smooth and consistent operation on your mountain bike. It is very similar to the Box One version however, to be more wallet-friendly, it offers a non-adjustable Tri-Pack Clutch, bushing pulleys, and some muted finishes. Box Two rear derailleurs are still optimised for 11-50T cassettes and offer durability and performance for the most demanding terrain, just at a lower price.FAQAre Box Prime 9 derailleurs compatible with Shimano “direct mount” hangers? No, Shimano direct mount hangers are proprietary and are not compatible with Box derailleurs.Is the Box Two Prime 9 Derailleur compatible with other 9 speed components? No, traditional 9 speed systems use a Cable Pull that is not compatible with Prime 9.Are Box Prime 9 derailleurs compatible with drop bar (road) shifters? No, Box Prime 9 derailleurs are not currently compatible with drop bar shifters, but we do offer a clamp for our shifters to mount on some 31.8mm drop handle bars.How should I clean my Box Two Prime 9 derailleur? We suggest removing the derailleur from the bike and using a soft bristle brush or rag with soapy water or a mild de-greaser. We do not recommend pressure washing, strong solvents or de-greasers as they could degrade the surface coating.Features: Material: Stainless Steel, Hardened Alloy Steel with Matte Onyx finish Tri-Pack Limited Slip Clutch Sealed Bushings Pulleys Nylon Composite Knuckle Pivot-Tech Cable Stay Durable 3D Forged Linkages Forged Inner and Outer CagePrime 9 TechnologyCompatible with Standard Derailleur Hangers (Non Direct-Mount) Compatibility: Box One Prime 9 11-50T Cassette Black Box Two Prime 9 11-50T Cassette Black Box Three Prime 9 11-50T Cassette Black Box One Prime 9 Chain 126L DLC Black Box Two Prime 9 126 Link Chain Nickel Box Three Prime 9 126 Link Chain Polished Box One Prime 9 Shifter Black Box Two Prime 9 Shifter Black Box Three Prime 9 Shifter Black Weight: 290gBuy Box Components from Chain Reaction Cycles, the World’s Largest Online Bike Store.