US AIRBOSS DEFENSE 40MM P100 GAS MASK FILTER NEW. Available in quantities of 1 or 20. In original plastic pouch with sheet. Add this Airboss America NIOSH Gas Mask Filter to any compatible 40mm NATO connector. Compatible with 40mm NATO-thread respirators. Designed to filter particulates. P100 filtration efficiency (>99.97%). Dimensions: 2.2″ x 4.23″. Weight: 3.1 oz. Connection: EN 148-1 (40mm) NATO thread. Country of Origin: USA. Condition: New, never issued. No sales outside the US.