Puerto Mask:Tempered Glass: Meets all ANSI standards; PLYFLEX skirt and strap: Durability and Comfort; Pivot Buckle: Adjust to strap angle for better fit; Quick adjust strap: Pull strap to tighten and push button to loosenPuerto Snorkle:Splash top: Keeps spashed water from easily entering tube; Purge Valve: Easily clear any water from snorkle; Flex tube: Allows snorkle tube to adjust for better fit