MSA Advantage 1000 NBC Gas Mask 813860 Size Small Fully Functional Old Stock. 1x Open Box Advantage 1000 NBC Gas Mask/Respirator. These masks are unused, the perimeter of the lenses have yellowing. Protect law enforcement and military personnel from a variety of respiratory hazards with the Advantage 1000 / Riot Control gas mask. Featuring flexible lenses, wider field of view, permeation-resistant construction and built-in speaking diaphragms, these masks provide protection with a comfortable fit and superior visibility. Attracts, regains and neutralizes contaminants. Flexible lens with a wider field of view for superior visibility. Easy on/off and adjustment with 6 point elastic / textile harness. Government, Fire Service, Police / Military. CBRN Incidents, Civil Disturbances, Clandestine Labs.