This dry recovery filter is meant to be used with the Trusted Clean wet/dry vacuum, and only when recovering dry materials. It's purpose is to to not allow any sort of material to enter the vac motor. This filter or the reusable needs to be used in any sort of dry pickup. You need to use one or the other, but not necessarily both at the same time.

To switch from wet to dry recovery, you'll need to remove the assembly and then remove the blue , and allow the recovery to properly dry out. We recommend emptying your machine and letting it sit overnight with the vac motor head assembly removed to allow the recovery tank to fully dry out.