HQRP HEPA Filter 4-Pack for Miele S314 S316 S318 S323i S324i S328i S334i S336i S338i S344i Midsize Canister Vac Vacuum Cleaner + HQRP Coaster HQRP&reg; Four Filters plus HQRP&reg; Coaster; This Active filter is HEPA and retains 99.97% of particles down to 0.3 micron. The filter has a activated carbon layer to neutralize and absorb odors. 100% Compatible with Original filter; 2 weeks DOA replacement warranty!