Filter is designed to fit Shark NV350, NV351, NV355 and NV356. This product includes (1) foam and (1) felt filter. Works with: NV345C, NV350, NV350_26, NV350A_26, NV350C_26, NV350E, NV350Q, NV350T, NV350W, NV350W_N, NV350WC, NV351, NV351C, NV352, NV352C NV355 , NV356 , NV357 , NV358 NV360 , NV370 NV391 , UV440 , UV490 , UV500 , UV540 , UV541 , UV550