Standing for Durable Unified Bottom Bracket, or DUB for short, SRAM's latest push forward in crankset technology unifies all major bottom bracket standards under a newly introduced spindle diameter of 28. 99 millimeters, versus the previous 30 and 24-millimeter spindles used by SRAM. What that means is this trail and enduro-friendly XO1 Eagle DUB Boost Crankset is compatible with virtually any mountain bike, whether your frame uses a threaded, Press Fit, BB30, or PF30 bottom bracket. After its initial release, we could already hear the groans of riders used to being bombarded with ever-changing standards in the mountain bike world. But before you click away, just hear us out. By focusing first on bearing longevity and sealing, then designing the spindle diameter to meet these needs, SRAM was able to engineer a new crankset that's every bit as light and stiff as those with 30-millimeter spindles, but one that provides the increased durability of systems with 24-millimeter spindles. It's really a simple concept and one that elevates SRAM's Eagle DUB Cranksets to the top of the market with their optimal mix of lightweight efficiency, stiff pedaling, and robust durability across all twelve gears. Outside of this DUB standard, the XO1 Eagle DUB Crankset is ideal for aggressive trail and enduro riding disciplines with its Carbon Tuned lay-up, which is built stiff enough to maximize energy transfer without sacrificing overall toughness when you thrash and bash it across gnarly rock gardens. This specific XO1 Eagle DUB crank is for BOOST spacing only, meaning it won't work on older bikes with 12 x 142-millimeter rear axles. It's one of the lightest cranks in SRAM's line at a paltry 471 grams, only surpassed in gram-counting efficiency by the cross-country favorite XX1 Eagle DUB Crankset (which is the lightest in SRAM's line when combined with a DUB bottom bracket).