... of membrane, external PPshell, PP skeleton,do not add any adhesives. Pleated filter cartridge, using built-folding structure of membrane, ... external PPshell, PP skeleton,do not add any adhesives Pleated filter cartridge, using built-folding structure of membrane, ... into the overall hot-melt, do not add any adhesives Figure Dimension: apertureµm0.10.20.45125103060Filter area0.40. ...