EnviroCare Replacement HEPA Vacuum Filters for Hoover Fold Away Turbo Power 3100 HEPA Pleated Filter, Upright, Bageless, Widepath Vacuum Cleaners 1 Filter Replaces OEM#: 40130050, 43615090. EnviroCare Premium aftermarket Part #924 Approximately 5 1/2&quot; wide x 2 3/4&quot; inches tall. For all Hoover Foldaway models in the 51000 series and Turbo Power 3100 Change every 3 to 6 months.