Durable Material: Air Vent Made from 316 stainless steel material, polished surface, corrosion resistance, sturdy and durable to use.Size: the Round Air Vent measures 125mm(5inch) in diameter, 4 drill holes(3.5mm), easy to install; and the air volume is adjustable to meet your need.Adjustable Ventilation: Our Incoming air can be used for indoor exhaust. suitable for heating or ventilating a boat, mobile home or caravan, Adjustable ventilation, changing fresh air according to your needs.Application: The round ventilation grill can be used indoors as well as outdoors for anyone who needs adjustable ventilation. Heat can be generated depending on the food being grilled. Even garages can be optimally ventilated with these vent escutcheons. LRFR is committed to providing each customer with the highest standard of customer service.