Hega Activated Charcoal Pre-filter Wrap 7" Designed to Fit Filter Queen Defender 4000 Dp360 Designed to fit all Filter Queen Defender Models with 8 Lasts up to 6 months (3 months with pets or smokers in the home) Removes up to 300 noxious gasses and odors Main filter shown for reference only Sewn in velcro closure makes installing a breeze!