Sonic from K2 is a soft but supportive binding with ProFusion; a chassis that gives the binding a tilt of 3 degrees, which in turn provides a more comfortable and natural riding position. Above the midsole, an EVA footbed is added to increase the comfort factor and absorb vibrations. Sonic has a good amount of flex for easy edge-to-edge transitions and Gap EraserTM forward design to customize the feeling to your characteristics and performance.