An invaluable tool for assessing your output during long training rides, grueling intervals, and competitive races, the Race Face Cinch Power Meter Spindle offers the adaptable versatility of Race Face’s Cinch system while delivering cadence and pedal efficiency directly to your head unit or smartphone for analysis. Not only is the meter’s +/- 2% power accuracy on par with many industry leaders, but the Cinch Spindle adapts to a wide variety of cranks from both Race Face and Easton. This left-side power meter is safely tucked into your bottom bracket shell, ensuring longevity over crank arm meters prone to rock strikes and damaging impacts on the trail. The 400-hour battery life is impressive, outlasting many of the other gadgets and head units hooked up on our mountain bikes. When it’s time to recharge, simply pop off the port and plug in a USB cable to quickly juice this power meter. Dual Bluetooth low energy and ANT+ ensure seamless compatibility with today’s smartphones and head units, with Race Face offering a Cinch Power Meter app for both Apple and Android devices. Another feature to note is the power meter’s auto-start/stop function, which can be disabled from the app when you’re traveling to the trail head or race venue. The Race Face Cinch Power Meter comes with an antenna cap tool, crank extractor/crank bolt adapter, 8 – 16-millimeter hex adapter, USB charging cable, and installation/operation manual.