this year we took the Phase franchise to the next level with the Phase BOA? Pro. and this year we’re continuing the progression with a Step On? model. We added top-of-the-line tech to the simple. skate-inspired upper. starting with the Dual Zone BOA? Fit System paired with our patent-pending SUPERLOCK heel harness to eliminate heel slip and deliver a more responsive ride. We also fitted it with our R3 liner with PrimaLoft? insulation. our warmest and most responsive ever. Simply put. the Phase Boa? Pro Step On? is one of our most advanced boots ever.