As you know, rolling weight does more to affect how a bike rides than static weight. By that reasoning, the weight of your rims is more important than the weight of any of your other components and weight, or the lack thereof is what the Easton EC90 XC wheel is all about. For the EC90 XC, Easton uses its proprietary Armored Ballistic Compound technology. The material shares characteristics with military grade body armor. It's extremely tough, and because of that, Easton is able to build extremely lightweight rims from it. In fact, at just 1416 grams per pair, EC90s are about 280 grams lighter than their aluminum counterparts, and about 200 grams lighter than their closest competitors. That's not bad for a wheel that retains the strength and stiffness to easily stand up to all mountain and even trail bike abuse. The EC90 XC is UST ready. The rim is laced to Easton's M1 hub with 24 Sapim 2. 0 spokes. The M1 is updated this year with larger bearings and an additional support sleeve between the two main hub shell bearings.