The Window Screen That Filters, the Safeguard 20-36" Adjustable Window Filter 11" Tall - Style #1136, lets allergic people keep their double-hung windows open and enjoy pollen-free air. The Safeguard window filter keeps out dirt and dust, and has been tested 92% efficient at keeping out ragweed pollen. A coated, baffled filter design slows down incoming air to increase filtration efficiency, while reducing outside noise and keeping out wind, rain and snow. This expandable poly-fiber filter fits windows 20" to 36" wide, and seals around the frame for a tight fit. Built to last with molded endcaps, vinyl seals, and a warp-proof, rust-proof aluminum frame. Change filter cartridge every year or when discolored due to particle collection.
The Safeguard 11" Tall, 20‒36" Adjustable Window Filter comes with one (1) filter cartridge. Replacement filter cartridges sold separately.