HQRP® Kit: 1 HEPA Filter + 1 Foam & 1 Felt Filters; This HEPA filter is H13 filtration class and retains 99.97% of particles down to 0.3 micron; Foam & Felt filters are located exactly below the dust cup and protect the motor from any debris going into it; Compatible with Shark XHF350 / XFF350 Replacement; Compatible with Shark Navigator Lift Away models UV540, NV391, NV390, NV350, NV351, NV352, NV355, NV356, NV356E, NV357, NV358, CU500, CU510, CU520, ZU503AMZ.