The Sidi Mag-1 Boots feature an innovative internal brace system constructed from carbon fiber for the ultimate in support & light weight design. The Mag-1 Boots weigh in at 4.4 pounds each, or 17% less than the Vortice boots. An all new Micrometric Tecno 3 magnetic closure system makes adjustments quick & easy & the internal brace system provides ankle stability & flexibility. The rear upper is made in polyurethane & is assembled to the boot with two screws: one on the outside under the TECNO-3 Magnetic mechanism, the other on the inside which holds the micrometric adjuster strap. The screws support & block the internal support system which is made ??with carbon fiber beams, making up the frame of the boot. This system allows excellent flex movement front-to-back while being firm side-to-side. An all new Micrometric Tecno-3 magnetic closure mechanism is easy & quick to use as well as being highly adjustable & light in weight. The TECNO-3 Magnetic closures close the boo...