Description of Dynafit Zzero 4 U-MF Ski Boots '09 The ZZero 4U is the polyurethane version of our 4-buckle range. With its transparent red color, this is the most striking and most downhill-oriented boot in the collection thanks to the PU reactivity (the fact that they become stiffer when cold). Although its weight is slightly higher, it offers incredible freedom of movement on while touring due to it’s modern design. It is also the lightest 4-buckle polyurethane boot compatible with Dynafit bindings. It is supplied with a Multiform liner, the lightest traditional ski boot liner on the market, and with our super-lightweight Thermoformable Thermoflex liner. Features: Shell/ Cuff/ Tongue: PU, Pebax®, Rilsan PowerStringer: Rilsan Buckles: 4 Magnesium + Power Strap Forward Lean: 15,21° + release for walking Cuff Rotation: 30° Sole: DynaGrip Ultralight Weight: TF 1710g (Size 27,5) MF 1860g (Size 27,5) Binding: Dynafit Quick step-in / UNI Target group: Downhill-oriented skiers who expect top performance on descent, but who also wish to be able to cover large distances.