The SV1 Contour is perfect for any use; snorkeling, diving, and free diving. Features include: Fixed lower section so snorkel stays close to your mouth, a dual silicone mouthpiece that prevents over-clenching of teeth that would restrict air flow, a rotational mouthpiece with ratchet indicators, a conical flared top for high performance breathing and a Scupper valve in the lower assembly. Lightweight and small in design, this is the perfect snorkel for your versatile traveler!