The time has come for you to stop guessing your energy output, and start coming in with cold, hard numbers to provide the data you need to improve. Quarq's DUB Crank Arms enable you to make the switch from not-so-smart cranks to all of the data you could ask for, with a clean carbon layup that's featherweight and stiff, and compatible with all SRAM DUB Road bottom brackets. The crank arms themselves skip the high-tech gadgets, but enable you to pair your cranks with either a Quarq DZero DUB -or- DFour DUB power meter spider so you can customize your crankset to best suit your needs. But just because the gadgets aren't present in the crank arms doesn't mean they lack tech - Quarq crafts them with its Exogram hollow core carbon fiber to provide a sleek, strong platform to pedal on, so you don't have to worry about wasting watts to crank flex.