Avanti TL Side-view Edgeless Purge Mask/MK398 & Cobra 100% Dry Whistle Snorkel/SK680:
Side-view Edgeless Purge Mask:
Whistle Snorkel: A unique, 100% absolute dry design -- Patented upper valve keeps water from entering the snorkel. Allows air to easily enter snorkel for clean and unobstructed breathing. Specially designed cover guards against water splashing into the snorkel. When the dry snorkel is submerged in water, the patented hinged seal reacts to seal the snorkel, preventing water from entering. As you surface, the hinged seal swings open allowing air to enter.