4YourHome Shark XFF350 Navigator Lift-Away NV350, NV351, NV352 Replacement Filter Set, 1 Felt + 1 Foam Washable Reusable Foam and Felt Pre-Filter Replacement Kit Fits NV350, NV351, NV352, NV355, NV356, NV356E, NV357 Replaces Shark Part# XFF350 Eco Friendly designed to wash and reuse again and again