The new Sherwood Blizzard Pro is completely new design and ready for cold water. The Blizzard's new 2nd stage proprietary valve design has been tested in the most rigorous conditions and continues to perform extraordinarily well. Both in the laboratory and in conducted testing the Sherwood Blizzard has stood up to every test. The larger diaphragm and purge cover provide easy breathing. And the diver operated Venturi control allow the diver to adjust the setting. The Blizzard's 1st stage is a completely dry and environmentally sealed 1st stage that avoids 1st stage icing and maintains a clean interior. No gels or liquids to seal the Piston 1st stage design.