When you are going for diving or snorkeling, there are 3 essential items you need, Mask, Snorkel and Fins. On top of that, you can also get some optional extras such as Snorkel Vest, Towable Dive Flag, Fish and Critter ID Card, Waterproof Camera, Lycra Protection and a Mesh Bag to carry it all in.
The Diving mask is your window to the underwater world. It provides an air pocket so your eyes can focus and you can see clearly underwater. A good quality mask will have its lens(es) made out of high quality impact resistant (tempered) glass, not plastic and the mask skirt will be made out of 100% silicone, not some other material like rubber or PVC. Don’t buy a cheap mask – they may look the same, but the things you can’t see (quality of skirt and lens material) are just as important as those you can. It is one of your most important pieces of gear.
The snorkel lets you breathe with your face in the water. A snorkel should fit comfortably in your mouth with the tip at the crown of your head. The vast majority of snorkels will do this easily with minor adjustments, so your primary selection considerations are mouthpiece comfort and features.
Snorkels have many different mouthpieces, from the more rigid PVC to soft silicone, different sizes or the so called comfort mouthpieces. For comfort a mouthpiece should always be made using 100% pure high grade silicone, as it provides a soft flexible finish that is unlikely to rub or cause irritation even after prolonged use。
The top of the snorkel will either be a simple opening or will have a wave deflector or dry top valve fitted. The simple opening is the most efficient option and allows unrestricted flow of air in and out of the snorkel. A wave deflector effectively caps the top of the snorkel and works to direct water that splashes over the top away from the snorkel opening. A dry top valve uses the outer design of a wave deflector to push splashed water away from the snorkel opening but also features a float mechanism that will shut a one way valve as the snorkel is taken below the surface, preventing water from entering the snorkel all the time it is underwater.
The main purpose of fins are to provide a large surface area to push against the water allowing you to swim using your powerful leg muscles to move you more efficiently through the water and frees your hands. Snorkeling fins should also provide some floatation for your feet which helps to keep you horizontal on the surface.
There are two types of fins, full foot and adjustable heel. Full foot fins are designed to be worn with bare feet (or thin finsocks) and are ideal for warm water snorkeling and diving. Adjustable heel fins are worn with boots and are ideal for diving in colder waters where thermal protection is needed or when entry and exit from the water is over sharp ground and would cause discomfort if walked across in bare feet.