Our N235GSM Respirator like mask combines 65gsm and 170gsm 3ply non-woven 100% polypropylene fabrics, features Guardian brand industrial thread, treated with Microban® Antimicrobial Product Protection stitching. At the top and bottom are encased steel wires to mold the mask to the wearer's face. Foam lines the inside perimeter for a complete seal against the face and comfortable fit. The style of the mask allows for maximum coverage while minimizing bulk. For the over the ear style masks, a velcro strap is in included to join the ear-loops behind the head and further adjust the seal and fit of the mask.