3M 6501Ql Reusable Half Mask The 3M 6500 Series Reusable Half Mask has been designed with tough & dirty work environments in mind. It delivers comfort durability & stability with a firm, lightly textured silicone faceseal and strong body construction. Quick to remove & refit. Comfortable in tought environments. Built to last. Works well with other PPE. Four point adjustment head harness.