1.Drill-free installation:This vertical window exhaust fan fits all standard sliding windows a great pick for renters avoiding window damage. Measure the clear height of the window frame pull out the brackets (6cm per side) and click it into place No drilling no damage Screws included for optional permanent mounting Horizontal vertical or side mounting possible 2.Adjustable fit for a perfect fit:Comes with 6cm stretchable side frames to match most sliding windows in houses and apartments Only one quick measurement is needed before installation It brings in fresh outdoor air and swiftly vents bathroom dampness kitchen grease fumes and stubborn household odors to keep your indoor air dry and clean all day 3.Powerful high-speed extraction:Dual fan design boosts airflow paired with a 2800RPM premium power drive unit, imported chips and durable hydraulic bearings for strong ventilation It rapidly eliminates cigarette smoke cooking smells pet odors and humid air refreshing stuffy rooms in minutes perfectly fit for families with smokers and pets 4.Ultra quiet operation and stepless speed control:Featured with the 6th-gen brushless magnetic bearing power drive unit it operates ultra-quiet with little vibration and no harsh buzz The stepless speed controller adjusts airflow from soft breeze to strong suction freely Low noise makes it perfect for bedrooms and living rooms letting you sleep and work peacefully without interruptions 5.Removable washable grilles for easy cleaning:Different from non-detachable traditional exhaust fans its double steel grilles can be taken down without tools for deep cleaning The full waterproof shell allows direct water washing to clear grease dust and pet hair easily Regular cleaning sustains steady ventilation performance and prolongs the fan's service life effectively