EN 143 Type P (3R) EN 14387 Type P (3R). RS Pro P3 Particle Filters. RS Pro P3 particle filters are bayonet connection filters and are type P. The filters have a class of P3R and are excellent for filtering any dust and particles. The filters are suitable for various half and full reusable face masks plus are interchangeable. FEATURES and BENEFITS:. Interchangeable P3 particle filters Type P Filters dust and particles Fit full and half face masks. APPLICATIONS:. Respirator face masks – Bayonet connection P420 P430 P500 P510