Filtrete Clean Living Basic Dust Filter, MPR 300, 20 x 20 x 1-Inches, 6-Pack Filtrete clean living filters are electro-statically charged to help capture more particles from your air. Attracts and captures large particles like lint & household dust from air passing through the filter Designed with Filtrete brand 3-in-1 technology from 3M to pull in and trap unwanted air particles while letting clean air flow through Microparticle performance rating 300 Outperforms fiberglass, Washable and non-electrostatic pleated 1 inch filters Lasts up to 3 months