K2 Sonic Binding - 2012: Go light on the wallet and heavy on the fun! The K2 Sonic booms with features that send shockwaves of progression pulsing through the veins at a price that will have you second guessing the sanity of both K2 and their authorized dealers like us, the US Outdoor Store. Built on a Pro-Fusion chassis and coupled with the proven Airfram highback, the K2 Sonic Bindings provide durability with a forgiving side-to-side flex. Stomp, tweak, poke, prod; whatever your poison may be, the K2 Sonic shall see it done.