The Trinity 110 Vacuum is snug like a plug boot but with a real world expert's flex rating, lighter weight, and a new and much-improved Ultralon padded liner. And oh yeah, there’s that whole Vacuum custom boot whiz-bang thing. A pneumatic bladder jacket compresses around the Vacuplast shell contouring it around wide and bony spots while growing only slightly tighter in less snug zones for an almost painted-on shape. That Vacuum process makes the boot fit like a glove and perform like a bobsled on rails, testers said. Testers who tried on the boot in its stock set-up found it had an aggressive forward-leaning stance. Those who made a point of utilizing the most upright setting during the molding process were the happiest with their final fore-aft stance. Tester Comments: "Skis like a race boot but with much more comfort." "Fully custom fit makes it maneuver precisely and respond quickly."