The Guardian Full Face Mask was designed by an Ex Navy Diver and made for the toughest conditions ranging from Military, Public Safety and Recreational applications. Removable 2nd stage for easy cleaning and storage One-piece, double sealed silicone skirt for extreme ruggedness Double face seal to fit a wide range of facial sizes and shapes Highly customizable equalizing block to make equalizing easy and comfortable Fog free visor design. No need for a defogging agent Utilizes a standard LP scuba hose Communications port for easy installation all of OTS’ communications Ambient Breathing Valve for conserving tank air on the surface Mask Bag and LP hose included Additional Information The components used in the Guardian second stage regulator are compatible with Nitrox use. Please ensure that the second stage and all components have been thoroughly O2 cleaned and lubricated with O2 compatible grease such as Christolube before use. See how easy it is to set up and use. See how easy a conversation is underwater.