【High quality stainless steel adjustable ceiling ventilation 】Outer diameter 125 mm - drill holes 3.5 mm - for 100 mm ventilation pipe - material thickness 1.0 mm Made of high quality stainless steel, environmentally friendly, safe, sturdy and durable to use. 【Easy to install Single round wall air outlet 】The ventilation plates are easy to assemble with their 4 drill holes. Very easy to install and the air volume can be controlled to meet your demand by using the control valve of our vent, convenient. 2 pieces - regulator on the side - adjustable stainless steel fan flies or other insects become annoying. 【Adjustable ventilation 】Can be used perfectly for indoor exhaustion, less noise and can also be used for decoration. Perfectly suited for heating or ventilation of a boat, mobile home or caravan If you want to supply a room with fresh air as needed, then you are making the right choice. 【Sleek and modern, easy to clean 】Simple design, fashionable appearance, fine workmanship and