UM-16 Mask: 1-window design with wide field of view; Patented round edge skirt for increased comfort and better seal; 3-D strap for unprecedented fit; Five-position strap angle adjustor for micro-adjustment; USP-250 Snorkel: Pure Silicone Flex-Neck and Mouthpiece; Patented Hyperdry Elite Dry Top Technology; Large capacity drain chamber and purge valve for easy clearing; Ortho-consciously designed mouthpiece for ultimate comfort