Features: 1.Function: For Zehnder, Helios, Maico, Pluggit Ventilation Valves - For Exhaust Valve/Butterfly Valve Ventilation Units, Cone Filters for Bathroom or Guest Toilet Ventilation Systems, High Quality Cone Synthetic Filters Without Adhesives Fleece standard size, easy to install. 2. Product size: Length 180mm, DN: 125mm, perfect fit of filter fleece, tested quality, premium tapered synthetic fleece. 3. Filter grade G4 about 8mm thick, professional quality for best air filtration and shatterproof, filter replacement ensures the best protection for your fan, eco-friendly and disposable. 4. Clean treated seams and maximum tightness, no air leakage from filter inserts, extractor filter, optimal energy efficiency and minimal noise. 5. Our filter is easy to install, no adhesive, thermal bonding; Specifications: Name: Conical Exhaust Valve Filter Set Material: filter cotton Packing size: 20*10*10cm Weight: 50g/100g Packing Quantity: 10pcs/20pcs Package Contents: 1*set of conical exhaust valve filter Note: 1. The real color of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness. 2. Please allow slight manual measurement deviation for the data.