Single-Component Baseplate Construction- One material throughout creates consistent response and feel for all-terrain domination. * Single-Component Hi-Back Construction- The simplicity of a one-piece hi-back means immediate response. Through material blends we then manipulate the overall flex profile-from buttery to responsive. * Living HingeTM Hi-Back- This exclusive technology eliminates hardware and weight, and allows you to adjust your Forward Lean and hi-back rotation independently. * LushstrapTM- Lushstrap Construction. 3D® Curved, Triple Axis Spine. EVA Padding. * Primo CapstrapTM- 3D® Curved, Triple Axis Spine. Grip Fit. * Smooth Glide Buckle Technology- Lightweight aluminum and lightweight polycarbonate levers give you season after season of buttery smooth and reliable ratcheting power. Designed and built by us, not some shady supplier. * Re:Flex FullBED Cushioning System- FullBED cushioning offers a full coverage, cushioned platform that maximizes comfort while minimizing fatigue. Anchored to the baseplate, its stealth trap door design makes it easy to access the mounting hardware. * Medium= US Boots Size 8-11 * Large= US Boots Size 10+