Designed for athletic hunters and outdoor enthusiasts of all types to move fast and with confidence on tough terrain. Apex is built with an innovative construction for high-endurance treks that require a more athletic and agile boot while still providing comfort and waterproof protection. 100% waterproof construction coupled with breathable mesh linings to provide elite protection and moisture management. Surprisingly light-weight performance for great all-day comfort and fit. Equally at home on loose rocky terrain, cold/wet ground and of course, the MUCK. 100% Waterproof 4mm CR Flex-Foam neoprene liner is 100% waterproof with exceptional comfort, flexibility, shock absorption and heat retention properties; adjusts to the contours of your foot to resist blisters and chafing Lace-up construction for a tailored fit Breathable mesh lining facilitates air circulation to improve comfort and reduce heat and moisture Dual density comfort footbed with memory foam for long lasting cushioning EVA midsole for lightweight comfort and shock absorption Lugged rubber outsole for durable traction bioDEWIX™ antimicrobial footbed insert topcover with NZYM™ for odor control and moisture management Pull-tab for easy on and off Estimated height: 11cm / 4.5in Estimated max calf circumference: 23cm / 9in Measurements were taken from a size 7. There may be slight variations based on size. Comfort Range: Sub Freezing to 65°F / 18°C 100% Waterproof 5mm Neoprene Bootie for Comfort and Performance bioDEWIX™ Antimicrobial Footbed Insert Topcover with NZYM™ for Odor Control and Moisture Management Breathable Mesh Lining Dual Density Insole for All Day Comfort Lugged Rubber Outsole for Durable Traction