The aero section on Jet 4 FR wheels is molded from a stiffer and lighter 1K fabric saving 30 g per rim. Flamme Rouge Sonic hubs are built to the same exacting tolerances as regular sonics but reduce weight with a carbon hub shell and forged titanium ratchet ring. Abec5 bearings are used for durability and low rolling resistance. Stability Control Technology is also applied to aero shaped wheels providing sure footed handling in crosswinds. Ride like a pro go Flamme Rouge. Ti skewers are lighter than stock steel ones. The Scandium alloyed rims on FR wheels are lighter stronger and stiffer than unalloyed models. Made with C2 platform rims bladed spokes and sonic hubs. Titanium skewers and a valve extender are included. The rider weight limit is 190lbs. The stallion build is available for riders 191-230lbs. Also available with Power Tap PRO+ SL+ and SLC+ hubs. This Aero clincher wheelset weighs 1553 grams / pair. Carbon and alloy silver hub bodies with black and white logos silver rims.