HQRP® 2-Pack Filter Kit Replacement for Shark XFF36 Foam & Felt Filter Set, Donut Shape; Kit Includes: 4 Washable Pre-Motor Foam Filters, 2 Post-Motor Felt Exhaust Filter; Before making a purchase please make sure your filter looks exactly like the one on the photo; If your original filter has no hole inside, our filter will not work with your vacuum cleaner; Compatible with Shark Navigator NV36, NV36A, NV41, NV4,2 UV410, NV44, NV44 26, NV46, NV46C Swivel Deluxe Upright Vac Vacuum Cleaner; Washable & Reusable; It is recommended that the filters be cleaned every 1-2 months for best performance, and make sure they are dry before re-installing.