SIDI Crossfire 3 TA BootSPECS TA= Traditional Application replaceable stitched sole Replaceable, adjustable calf plate Hinge pivot that glides to a hard stop to prevent hyperextension and hyperflexion Replaceable, adjustable shin plate to accommodate knee braces Replaceable Easy Action cam lock buckles with adjustable locking straps Shock absorbing heel cup adds protection provides and secure fit Closed cell foam provides a snug, secure fit for optimal comfort Air Teflon