This is the DUI DuoTherm II 300 Socks Divewear Insulation for Scuba Features: Maximum stretch & low bulk Recommended for 45-60AdegF great choice for a wide range of water temps! DUI&';s DuoTherm II 300 Socks uses double-layer all-way stretch fleece. Exceptional stretch and warmth. Available in sizes: S, M, L, XL, and XXL. Choice sock for sport and technical divers wanting minimal bulk.The updated version of DuoTherm II has our new Active Wicking Technology (AWT). Perfect for repelling water from incidental water contact while the moisture inside your suit is wicked away from your body.