Ridgid 3 Layer Micro Pleated Cartridge Wet/Dry Filter, Press Fit Technology, fits new and old style Ridgid vacuums. Pleated design resists clogging. Uses Press Fit Technology eliminating the need for the screw on attachment. Simply press the filter on and when the filter is due to be replaced, pull it off. Guaranteed Fit & Performance. Sold 8 filters per case.