Sealed Warmth and Durability. If you’re looking for the perfect balance of warmth and performance for a great price, the HydroFlex Series is the perfect fit. This Dive series offer ThermoLite IR lining which generates infrared warmth, vent holes, Glide Skin face seal and comfortable contoured chin, extended bib with protective stretch binding on the edges; ideal for layering, glued and blind stitched seams with reinforced stress points.