This series of filters with Dräger specific thread connection Rd90 (91 mm diameter) was designed for use in half masks. Suitable for Dräger half masks X-plore® 4390 and X-plore® 4790, via adapter 40/90 also for all masks with connection as per EN 148-1. Compact filters with aluminium housing to ensure reliable recognition of possible filter damage Individually packaged for optimum protection of the unused filter Shelf life (from date of production): gas and combination filters 6 years, particle filters 12 years Certifications: EN 141:2000 re. EN 14387, 143:2000); SAI Global-approved