HQRP Foam & Felt Filter Kit for Shark Navigator Lift-Away NV350, NV350nz, NV350_26 Series Upright plus Coaster HQRP Foam and Felt Pre-Filter Replacement plus HQRP&reg; Coaster; These filters are located exactly below the dust cup and protect the motor from any debris going into it; Do not operate the vacuum with wet filters; 100% Compatible with Original filter; 2 weeks DOA replacement warranty!