Features: Thermocarbon: Water-repellent, heat-retaining plush lining infused with renewable bamboo charcoal & recycled fibres; Pressure Bonded: Durable taped seams; Drylock: Engineered, seamless ankle seals that prevent flushing & seal heat in; Cut-out sole for maximum flexibility & a lightweight design; Stitchless inside boot, water never penetrates through neoprene; Velcro cinch across instep plus horizontal flex heel support for a secure, snug fit; Pull loop is secured to boot without sewing through neoprene; Engineered for maximum warmth & performance; Xcel use limestone as the base component for all of their neoprene & glue. Powered by clean hydro-electricity, the waste heat generated by the limestone conversion processes is then re-purposed for aqua farming. Making excellent quality equipment while being environmentally conscious.