Single-ring drivetrains offer numerous benefits compared to 2x systems encumbered by a front derailleur: quieter operation, less maintenance, simplified shifting, and much better chain retention. Occasionally you might run out of gears on a tough climb or a fast descent, but that changed when SRAM released the Eagle 12-speed group. With a 520% gear range that rivaled 2x drivetrains and some of the best mechanical shifting we've ridden, it's no wonder that Eagle took the market by storm. Cost was high for the initial release of XO1 and XX1, but then SRAM gave us GX Eagle which made 12-speed attainable for the price-conscious rider. This GX Eagle DUB Groupset includes everything you need to put Eagle on your bike, except for an XD driver for your hub and a SRAM DUB bottom bracket. This groupset comes with the crankset, cassette, chain, rear derailleur, shifter, and b-gap adjustment tool. The crankset is light and sturdy, comprised of 7000-series aluminum rather than carbon, helping keep the cost down. It comes with a 6mm offset chainring for non-Boost bikes with QR or 12x142mm rear spacing. The crankset features the DUB spindle, which SRAM claims is stiffer than GXP and lighter than BB30. DUB is compatible with virtually any frame if you get the right DUB bottom bracket (not included).