Connelly incorporated everything they know about skiing into the Sonic slalom ski. The sidecut is wide in the tip and narrow in the tail. Hook grooves on each side of the tunnel, 6 V-shaped steps, for a more efficient, faster feel on the water and the most forgiving flex pattern ever created. Together this makes the Sonic ski extremely easy and fun for skiers carving up the lake. The Connelly Sonic features CAPT construction with closed cell polyurethane resin core. Hand-tuned Acrylam base. Aluminum drop-through fin with foil. Nova lace adjustable binding features a thick EVA heel rubber wrap with achilles pad that holds down your foot. Nova Binding sizes: S/M(5-11), L/XL(9-14).