This is the Tilos 6mm Thermowall Hi-Tract Semi-Dry Scuba Diving Boots Bootie Features: 6mm lined with Thermowall lining enhance heat retention & quick-dry feature 8.5" (21.6cm) lengthened height for extra warmth & protection Water barrier YKK #8 zipper High rubber toe cap Internal double smooth-skin seal flap at zipper reduces water entry Glideskin entry seal Built-in strap stopper Double glued and blindstitched New Hi Tract sole design gives your feet extra traction on wet surfaces