The Advantage 420 Half-Mask Respirator is uniquely designed to incorporate user-friendly features including maximum comfort, improved donning and fit, enhanced safety, and reduced maintenance cost. The Advantage 420 Respirator has a Patent-pending UniBond over-molded one-piece silicone facepiece, helping to eliminate possible leak paths which may be present in other competitive silicone half-mask respirators. All plastic MSA Advantage cartridges as well as metal MSA Comfo® threaded cartridges can be used with the Advantage 420 Respirator.