SRAM Force AXS D2 DUB Power Meter Upgrade Crank ArmSRAM Force AXS D2 DUB Power Meter Upgrade Crank Arm Power measurement is a crucial part of training, so weve made it as easy as possible to upgrade your Force AXS ride with Quarq technology. DUB PWR takes the legendary reliability and accuracy of Quarq technology and inserts it into the crank spindle for clean integration that fits more bikes than ever. Its invisible technology that adds minimal weight and will help you get to the finish line faster.