SRAM cut grams out of their Rival aluminum crankarms, but didn't cut corners on power measurement. The light and accurate spindle-based power unit nestles into the striking redesigned arms to give you the data you need, and our newest direct mount chainrings are light and stiff while looking good.Spindle-based power meter unit measures left side power to calculate total wattsLong battery life (400+ hours) to power a season of rides (User replaceable AAA lithium battery)IPX7 waterproof to 1 meter for 30 minutesX-Sync wide-tooth, narrow-tooth aluminum chainring technology provides maximum chain controlCarbon fiber crankarms are incredibly strong and lightweightDUB bottom bracket adds durability and simplicity (Bottom bracket sold separately)150mm Q-factor / 47.5mm chainlineItem SpecificationsBB IncludedNoChainline/Hub Compatibility135/142 Road Disc Hubs < 415 mm ChainstayChainline/Hub Compatibility135/142 Road Disc Hubs > 415 mm ChainstayChainring BCDDirect Mount SRAM 8-BoltColorBlackCrank Intended UseGravelCrank Intended UseRoadCrank Length (mm)160Defined ColorBlackDrivetrain Speeds12Drivetrain Speeds13Number of ChainringsChain Retaining SinglePedal Spindle9/16"Rings42Spindle Interface TypeSRAM DUB SRAM Rival 1x XPLR AXS 12/13-Speed Power Meter Wide Crankset E1 Crankset UPC: 710845916069