Description of Silvretta Pure FreeRide w/90mm Brake:
Silvretta designed the Pure Freeride Binding eih 90mm Brake for backcountry skiers who don't want to sacrifice downhill performance. For comfort and natural movement while touring, Silvretta moved the pivot point 30mm behind the tip of your boot to save your precious energy. These lightweight AT bindings' two climbing positions make that final steep pitch a breeze. With maximum torsion resistance and a DIN that goes up to 12, this binding just begs for the powdery descent. The 90mm brake fits over your more rotund touring sticks.
Bottom Line: Leave the resort behind and really ski free with the Silvretta Pure Freeride Binding on your hiking skis.
The writings about this say that only the heel releases, meaning there would be no lateral release (sideways). That would be really bad and dumb. In reality, when you go sideways, the wings at the toe push the heel out and to the side, so the heel exits the side of the heel piece. (Somewhat like a dynafit, only by going backwards instead of rotating).
Just in case you're curious, here are the boot lengths sizing:
S: 265-305mm
M: 300-340mm
L: 335-375mm
Will write a full review once I get a chance to hit the snow with these in 2010.