A 2mm thick hood that fits like an "over-hood" that protects all exposed areas of the skin. The holes for the mask and the breathing device can be perfectly adjusted by the user.
It also offers excellent protection against jellyfish in infested waters.
A clever solution: just pull the H1 Icehood over the normal neoprene hood to get additional protection in really severe cold water immersion conditions. The H1 Icehood is also easily adaptable for use in tropical and warm water conditions, just cut out the parts of the face to create your own custom hood.