No matter your skill level or experience on the bike, there's no better way to enhance your training and racing performance than by riding with a power meter. And for all of you Dura-Ace fans out there, we've combined our extremely light power sensors with a Shimano Dura-Ace crankset to give you the most accurate and precise power meter available.The development of Power Cranks began with our Human Performance Team looking at riders in realistic scenarios on the bike. Historically, power meters have been validated by two different methods—one is by measuring the produced torque by applying a static, linear load to a crankarm or chainring, while the second uses a power generating motor to pedal the bike. Well, cycling is neither static nor linear, and humans apply power much differently than a machine. So, we found that neither of these methods answers the 'real-world' accuracy question.To get the best test for accuracy, in all types of riding scenarios, we built our own cycling treadmill, the WinMill, to measure power output to a known truth. This new benchmark lets us evaluate accuracy under all riding conditions—seated versus standing, various power and cadence levels, different weights, and a myriad of gear. This data acquisition process is our gold-standard for testing power meters, and through our testing and external validation from the Locomotion Lab in Boulder, Colorado, Power Cranks have been proven to have the highest accuracy in real-world scenarios (+/- 1.5%).The Dual-Sided S-Works Power Cranks utilize separate strain gauge systems to individually measure the effort produced by each leg. This maximizes the accuracy of your total power numbers, plus it helps you to better understand your performance as fatigue increases and when you're recovering from injury. And with class-leading temperature compensation firmware and waterproof enclosures, Power Cranks are easy to live with. Calibration is only required during seasonal-type fluctuations in temperature, and the included wrench makes battery swaps a breeze.- +/- 1.5% real-world accuracy tested on the WinMill and validated by the Locomotion Lab in Boulder, CO- Independent, dual-leg power measurement- Works with ANT+ and Bluetooth devices- Easy set-up and diagnostics with the Specialized Power app. (iOS and Android versions available)- Available in 170-175mm crankarm lengths- All models include 52/36T chainrings