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Never dive alone; make sure you have a partner who will be with you the entire time you are in the water. The “buddy system” is essential to freediving safely. Your buddy is responsible only for you and you are responsible only for them. One partner is always on the surface monitoring the diver and ready to provide aid if necessary. These are crucial pieces of equipment for freediving, and it is important to choose masks and snorkels that are comfortable and securely fit your face.  An air mask should be low volume. When freediving, you will need to equalize which involves exhaling through your nose to balance the pressure. With a low volume mask, you don't not have to exhale very much to equalize; this means you use less oxygen.  Air masks should be made of tempered glass so they withstand the water pressure without breaking, and they should fit securely to your face. To test the fit, hold a mask to your face then breathe in gently through your nose. If the mask remains on your face after a few seconds, it is a good fit.  Snorkels should be easy to remove and comfortable to wear. For convenience sake, look for a snorkel that will attach to your mask. Fins are another important part of freediving gear. They help you to move efficiently under the water. There are two types of freediving fins: bi-fins and monofins.  Most beginners should start with bi-fins. These resemble scuba diving fins but are longer. Most beginners choose soft or medium-soft blades. Make sure they fit securely and are comfortable, as you will wear them throughout the entire dive.  A monofin is a single fin that you place both feet in, like a mermaid tail. They are more effective than bi-fins, but much harder to master. Weight belts are belts designed to have diving weights easily clipped to them. These weights prevent you from floating to the surface as you dive. Lanyards are used to attach you to the line. This helps guide your descent, and it is an important safety device. If you black out or need assistance, your partner can travel down the line and know precisely where you are located.  Not all freedivers use weights or lanyards, but they are useful pieces of equipment, especially for beginners. If you are diving with a class or group, a line or buoy will most likely be provided. If you are diving in cooler temperatures, an exposure suit and gloves will be necessary.
Find a buddy. Buy your air mask and snorkel. Purchase your fins. Buy your weight belt and lanyard.