RZ Mask Dust Mask, Gender: Mens/Unisex, Primary Color: Black, Distinct Name: Black, Size: XL The RZMASK is made of a Strong Neoprene outer mask with replaceable inner filters It offers two discharge air valves to allow for maximum breathing comfort Easily adjustable for a custom fit The Velcro strap allows for a simple quick placement and removal, which makes the RZMASK very comfortable for hours of use It also offers a pocket on the back strap to allow for a MP3 player to be conveniently and safely held for those who enjoy listening to music