The top of the line ski in the WStudio performance line, the Amphibio Insomnia uses Amphibio technology and Waveflex for longitudinal flex and torsional rigidity. It has a monolite wood core and a single sheet of metal, so it' s light and stiff. The tips of the new Amphibio skis are tip-rockered on one edge, but not the other. You could call it "twist rocker." The idea is to have aggressive camber on the downhill ski with a looser feel on the uphill ski. Testers suggested mixing and matching to suit conditions-rockered edges inside for soft-snow, cambered edges inside for hard snow. Waveflex cores use a wave pattern (think corrugated carboard) to keep them flexible longitudinally yet stiff torsionally.