The new Sherwood Oasis Pro is a completely new design and ready to provide you comfort and easy breathing in all diving conditions. The Oasis'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 Oasis has stood up to every test. The proprietary Moisture Retention Vane does an outstanding job capturing exhaled moisture and returns it upon inhalation. No more cotton mouth with this regulator! The larger diaphragm and purge cover and responsive to inhalation provide easy breathing throughout the dive. And the diver operated Venturi control allow the diver to adjust the setting. The Oasis 1st stage is a completely dry and environmentally sealed 1st stage maintains a clean interior. No gels or liquids to seal the Piston 1st stage design.