Sram GX Eagle Dub Boost 12 speed group kitKit includes:GX Eagle 10-52t compatible Rear DerailleurGX Eagle Trigger ShifterBoost spacing Sram DUB Crankset - available in 170mm or 175mm lengthsEagle GX Hollowpin ChainEagle GX 10-52t CassetteChain gap gauge175x32 Boost DUBLunar GreyUPC/EAN/GTIN: 710845853319