The fastest way to fill your lungs with air, this snorkel has a lovely comfy silicone mouthpiece attached to a large-bore snorkel tube. A stock standard diving snorkel has an internal diameter of 20-21mm... Some cheaper kids snorkels even go down to 15mm. This Wide-Bore compares with an internal diameter of 25mm. It makes a big difference to how quickly and easily you can pull in air, and takes a few minutes to get used to... but the proof is once you've tried a Wide-Bore for a while, then try switching back to your regular snorkel... It's like trying to breath through a straw. A must-have for competitive players.