their brand new "Step On" binding and boot system. Speed entry (hybrid) There are also proprietary systems that seek to combine the convenience of step-in systems with the control levels attainable with strap-ins. An example is the Flow binding system, which is similar to a strap-in binding, except that the foot enters the binding through the back. The back flips down and allows the boot to slide in; it's then flipped up and locked into place with a clamp, eliminating the need to loosen and then re-tighten straps every time the rider frees and then re-secures their rear foot. The rider's boot is held down by an adjustable webbing that covers most of the foot. Newer Flow models have connected straps in place of the webbing found on older models; these straps are also micro adjustable. In 2004, K2 released the Cinch series, a similar rear-entry binding; riders slip their foot in as they would a Flow binding, however rather than webbing, the foot is held down by straps. Highback A stiff molded support behind the heel and up the calf area. The HyBak was originally designed by inventor Jeff Grell and built by Flite Snowboards. This allows the rider to apply pressure and effect a "heelside" turn. Some high backs are stiff vertically but provide some flex for twisting of the riders legs. The highback adjustments allow the rider to implement a higher degree of forward lean. These settings are usually calibrated between F1 (the lowest lean) to F5 (the highest lean). Implementing higher levels of lean are directly proportional to the riders skillset and type of terrain. Plate Plate bindings are used with hardboots on Alpine or racing snowboards. Extreme carvers and some Boarder Cross racers also use plate bindings. The stiff bindings and boots give much more control over the board and allow the board to be carved much more easily than with softer bindings. Alpine snowboards tend to be longer and thinner with a much stiffer flex for greater edge hold and better carving performance. Snowboard bindings, unlike ski bindings, do not automatically release upon impact or after falling over. With skis, this mechanism is designed to protect from injuries (particularly to the knee) caused by skis torn in different directions. Automatic release is not required in snowboarding, as the rider's legs are fixed in a static position and twisting of the knee joint cannot occur