HQRP 2-Pack Post Motor Filters for Bissell 58F8, 18M9, 26T5 Rewind SmartClean Vacuum plus Coaster HQRP&reg; 2pcs H11 Post-motor media filter plus HQRP&reg; Coaster; This filter is H11 filtration class and retains 95% of particles down to 0.3 micron. Dimensions: 7.25" X 2.25" X 0.5". Recommend replacing your vacuum filters every 3 to 6 months Compatible with Original filter; 2 weeks DOA replacement warranty!