Your lean, mean, trail-to-river machine. Flyweight Men's Wading Boots cut ounces in exchange for maximum output, relentless grip, and standup stability and comfort. Optimized for best-in-class wet-slip resistance, the Vibram Idrogrip Flex outsole is engineered with a rubber compound that is softer and therefore grippier than the sole materials in other Simms wading boots.