Fits easily in both of my shop vacs. The manufacturer of this secondary filter has designed it in such a way that it does not require a loose end cap that always has to be screwed onto a standard Shop-Vac filter. The plugged end is an integral part of this filter and a simple press fit holds it securely to the vacuum motor. Whether this filter is more durable than the standard filter after washing, I can't say yet. Although the two materials appear similar, I give Multi-Fit the benefit of the doubt in my review as it is advertised as washable.