The 3 quart paper bags are designed for the Lindhaus DP-5 HEPA and Valzer HEPA series uprights. These uprights have a tube along the left side inside the bag chamber. The Filtrete exhaust filters measure 5 1/2" x 4 1/2". One filter fits in a frame which is covered by a lid on the front of the vacuum's main body. For similar products see our list of Lindhaus Vacuum Supplies.