Whale SK-100 Dry Snorkel Snorkeling with Purge Valve, Flexible Mouthpiece & Quick-Release Removable Mask Strap Clip - for Swimming, Diving, Snorkeling Whale SK-100 Dry Snorkel With Silicone Flexible Mouthpiece and Purge Valve for Snorkeling and Scuba Diving . Patent design for back exhaust, bubbles don't affect the lind of sight. One way purge valve can drainout the water and CO2 Floating Ball:its dry top has a floating device design that closes the openning while the snorkel submerges under the water , and it re-opens after the snorkel comes back to the surface. Easy loading and unloading button Connect or disconnect your mask with ease using the quick release clip