a legendary all-mountain binding for women. the union trilogy classic is not only the best-selling model of all time, it is above all comfortable. its components are designed for all-mountain riding from piste to park to powder. union improves this model year after year to offer you state-of-the-art performance. highbackthe duraflex st force highback gets thinner towards the top, giving freedom for tweaks while still keeping the binding responsive. the angle of the highback (forward lean) can be adjusted without tools.baseplatethe stage 4 baseplate with medium to hard flex, is made of duraflex st nylon. this material offers stiffness and responsiveness that will last season after season. the multi-density, thermoformed eva bushings provide excellent cushioning, even in cold temperatures.strapsthe exoframe 4.0 ankle straps are the ultimate connection between boot and binding. the progressive flex allows for quick response and power transfer for demanding riding at high speeds. the thermoplastic anti-slip material of the wide ts-2.0 toe straps keep your boots bombproof and secure in the binding. the straps come with magnesium buckles. they are 4 times stronger and twice as light as aluminum buckles.