only suitable for snorkeling, cannot be used for scuba diving The main obstacle to snorkelling is the difficulty in breathing underwater with a snorkel. Indeed, breathing through your mouth is unnatural, and the snorkel mouthpiece is sometimes considered too intrusive, uncomfortable and unhygienic. the full-face snorkelling mask, for breathing underwater as easily and naturally as you would on land with your nose and mouth. This is a replacement/compatible Gopro product To ensure that water does not enter via the snorkel, the mask is equipped with a mechanism that plugs the top of the snorkel when immersed in water. Furthermore, the top of the snorkel is highly visible in order to avoid any collisions on the surface. Surface mask, not suitable for free diving WIDE FIELD OF VISION----- 180° field of vision and shatterproof polycarbonate window for added safety. Easy breathing-----Full mask for natural breathing through the nose and/or mouth. Anti-fogging-----Exclusive breath ventilation concept prevents fogging. Impermeability / seal-----Dry top snorkel system stops water entering through the top of the snorkel. Water drainage-----Purge valve at the bottom of the mask to drain water when the head is raised. Easy dressing-----Adjustable elasticated textile strap does not pull your hair out. Visibility-----Snorkel top can be seen from 4 times further away than a traditional snorkel. Swimming depth-----Reminder: Surface mask, not suitable for free diving. Features: Double air-flow channel - inhaling and exhaling separate channels for anti-fogging. Broadside dual sealing design is from imitating human face, made of liquid silicone without skin irritation.

• S/M - innner diametre 17x13cm - external diametre 23x19cm Step 1. Measure the distance between Nose bridge to bottom of the chin. Step 2. If the distance is less than 12 cm (4.8 inches), Choose Small/Medium. Step 3. If the distance is more than 12 cm (4.8 inches), Choose Large/XL.