As with everything from AX Lightness, the Rigid Stem is engineered to the gills. You can't see most of what went into the stem, but you'll feel it. While AX Lightness builds its wheels from woven carbon fiber, it chose to use unidirectional carbon fiber for it's static components. This is because unidirectional fiber handles static loads better and woven fiber handles dynamic loads better. With this construction comes greater strength, lower weight, and a unique aesthetic. The fibers are run diagonally to optimize strength with a minimum of material. The stem's square cross section also adds stiffness, but the carbon fiber absorbs road vibration to increase comfort. For added safety, clamping areas are reinforced with 3K carbon cloth layers. AX Lightness then outfits the stem with titanium bolts and aluminum clamping hardware to cut down every possible gram.