This filter is very well designed, but is not a direct replacement for the Rigid specification. I call for the VF4000. Eventually I managed to get it to fit, but not without some ingenuity and scolding to carve enough under the lid to make it fit. The cage tower below the filter is slightly higher than this standard filter. Maybe better buy an adapter from Amazon "Kopach replacement filter cap for craft and rigid vacuum cleaners" (I haven't tried it yet, but it seems to fit for this filter by removing the end cap). However, you only need to buy this adapter once. I've posted a picture of the modification under the attached cover. Sorry, I should have photographed the original before I started. Hmmmm now it fits perfectly :) This is Katherine's husband.