The Sherwood Scuba Blizzard Pro is ready for cold water and ice. The BlizzardPro's 2nd stage proprietary valve design has been tested in the most rigorousconditions and continues to perform extraordinarily well.In the laboratory andin real work diving the Sherwood Scuba Blizzard has stood up to every test.The Blizzard's 1st stage is a completely dry and environmentally sealed thatavoids 1st stage icing and maintains a clean interior.This unique design doesnot require any gels or liquids to seal the Piston 1st stage design, unlikemany competitors.