High quality ventilation filter: using needle-punched cotton cartridge fabric. Special electrostatic filtration captures small particles and reduces dust in your home. They also prevent undesirable items from entering your home. Great value for money: Each package comes with 200 cm x 100 cm filter wool and 300 cm of double-sided, non-marking mounting tape. It can cover more than 36 standard exhaust vents. Cheaply covers non-standard larger size vents. Flexible DIY design: compatible with all sizes of vents, air vents and grilles. Cut to fit any size vent. This versatile design makes it easy to cover or install behind non-standard vent sizes and for DIY projects. Easy to use: simply glue the mounting strip to the outside of the vent and stick it in place. Easily replace dirty filters without removing the vent. Easy to apply and replace without restricting air flow. Product parameters: European standard G4 standard Product size: 200*100cm, package size: 30*20*1cm, weight: 240g Accessories parameters: filter cotton * 1 sheet + non-marking double-sided tape * 1 roll