The RIDGID Pleated HEPA Filter is designed to fit most RIDGID wet dry vacuums (3 to 4.5 gal.) to capture wet and dry messes. It can also be used with the RIDGID Ash and Grilling Vacuum (HDAV0500) to pick up cold ash. This HEPA Filter is 99.97% efficient at filtering dry particles 0.3 micron or larger. Increase your filtration level on the jobsite with this HEPA filter. During your heavy-duty project cleanups, the shop vac filter can be used to capture dry messes such as drywall dust, sawdust, and mold as well as liquid spills and waterborne debris. The durable, strong material allows for wet and dry messes to be picked up without switching between a dry and wet filter - saving you time and energy. With the Qwik Lock feature, the wet dry vac filter simply snaps on or off the shop vacuum for easy cleaning and this replacement shop vac filter can also be washed and reused for extended uses. Changing RIDGID shop vac filters often is strongly recommended to increase the vac's performance and to help extend wet dry vacuum life as it protects the motor from harmful debris. Pair filter with a RIDGID dust bag (VF3501) to contain dry dust and debris and for easy disposal. RIDGID wet dry vacs provide a wide range of filtration and attachment options so that you can customize to the job at hand.