FILTER PACKAGE Replacement filter package. This includes 2 filters. Primary filter This is the outside filter that goes around your motor. The Primary filter is made of fiberglass material so in case a warm ember enters the vacuum by accident, the filter will not start on fire. The Primary filter will withstand temperatures of 1200 degrees. Secondary filter the secondary filter is the smaller filter which goes underneath the primary filter. This is a high density filter for filtering what ash passes through the Primary filter. With the 2 filters in place, ash will be filtered before it can escape into your home.