It is recommended that you replace the filter every six months or as needed to help maintain vacuum function as well as maintain optimal filtration inside of your home. Stop washing your old foam filter round blocks all the time and get new， clean ones if you crave for faster and more efficient cleaning.<br /><br />Features:<br />1. Fit for Shark models NV350， NV350A， NV350E， NV350Q， NV350T， NV350W， NV350WC， NV350WM， <br />NV351， NV351， NV352， NV355， NV356， NV357， NV360， NV370， NVLFT199， UV440<br />2. Replaces for Shark part numbers XFF350<br /><br /><br />Specification: <br />Material: Foam<br />Color: White<br />Size: 17 x 16 x2.5cm<br /><br />Notice:<br />1. Please note that our high quality replacement filter is custom made and unbranded and that we have no association with the original Shark Nv500 vacuum cleaner suppliers. Our filter is a compatible replacement and not original.<br /><br />Package included:<br />1 x Foam Filter<br />1 x Felt Filter