With the expertise of 15+ years of power measurement, PowerTap looked to DT Swiss and their renowned reputation for quality and performance to join efforts in creating the PowerTap GS. The GS is everything you'd expect from a PowerTap hub, with the added bonus of the DT Swiss Ratchet System™ technology. From the press fit assembly with contact-free seals, to the DT Swiss bearings to the exchangeable rotor body, every DT Swiss hub is designed to transform a rider's energy into forward momentum. Combine PowerTap's +/- 1.5% accuracy with ideal strength-to-weight ratio and straight-pull spoke technology, you'll get a stiffer, more responsive, and better riding wheel. - PowerTap GS straight pull hub shell - 24-spoke rear - Weight: 320g - DT Swiss bearings - Compatibility: Shimano/SRAM or Campagnolo - Powermeter accuracy of +/- 1.5% - Field-serviceable electronics - ANT+ or Bluetooth Smart - Battery: CR 2032 - 9, 10, 11 speed compatible - Head Unit: You will need a Joule or other ANT+ compatible device to use this hub. Bluetooth Smart PowerCap is available as an accessory.

Stan's 3.30/3.30Ti Hub Kit converts Stan's 3.30 front hubs from quick-release to through-axle compatible. Installation is easy—just pull the old ones off and put the new ones on. Conversion kits available in 12mm and 15mm.

Stan's 3.30HD 15mm Hub Kit makes Stan's 3.30HD front hubs 15mm through-axle compatible. Installation is easy—just pull the old ones off and put the new ones on.

Shimano's Ultegra Hubs are flag-bearers for high-durability, smooth-rolling performance. Hardened steel cup-and-cone design use stainless steel bearings for minimal drag and superior ease of maintenance. Shimano's Digital Adjustment System makes hub maintenance fast, simple, and reduces axial force on the bearings, reducing wear and tear on the hub internals.

• Sealed cartridge bearings • High flange design • 120mm hub spacing • Aluminum hub body • Lightweight, hollow, heat-treated axle • Fix/freewheel hub threading • 32 and 26-hole spoke drilling • Bolt-on 3/8-inch axle • Black, silver, or white

SRAM's X9 hubs are built tough with light aluminum hubshells for the strength to tackle the mountain year after year. You'll love the durable high-precision cartridge bearings that spin smoothly in all conditions. Plus, careful machining helps keep the X9's weight low without compromising durability.

Analyze the power curve of your kilo, get the most out of your standing start, and see where you can conserve in the points race. The 331-gram PowerTap G3 Track Hub makes you faster with smarter training and racing. You can also track your Training Stress Score (TSS) and Chronic Training Load (CTL) for long-term gains and staying within your personal physical limitations to avoid over-training. The low-profile G3 hub is made of light, durable aluminum with wide flange spacing for increased stiffness. It's accurate to within +/-1.5% and is ANT+ capable for use with your favorite compatible cycling computer (sold separately). Plus, all the electronics are held within a small, easily removed outer cap.