... pre-filtration and single-stage filtration in the air systems of household vacuum cleaners, industrial vacuum cleaners, reciprocating air compressors ... or two part PU adhesive as the frame end coverFigures of column and squareness, etcLarge filtration area, high dust holding ... long life (washable), economical, utility, easy to install.Filtration efficiency class: G3, G4, F5, F6, F7, F8 Portable ...