3M Half Facepiece Reusable Respirator, Four-Point Harness, Comfortable Fit, Dual Airline Supplied Air Compatible, Bayonet Connections, Painting, Sanding, Cleaning. The 3M Half Facepiece Reusable Respirator helps provide protection against particulates and a wide variety of gases and vapors when used with approved cartridges and filters. When properly fitted and used with approved 3M cartridges and filters, this respirator can help provide protection at concentrations up to 10 times the Permissible Exposure Limit (PEL). The swept back design of the cartridges helps improve balance and visibility. Remarkably comfortable, soft, lightweight facepiece has easy-to-adjust head straps that allow for a customized fit to the user. Replaceable cartridges help reduce waste and costs over time.