Description: Premium Material: Our air duct filter cover is made of high quality material, which is waterproof, breathable and durable, so it will not be damaged in wet environment. Drawcord Design: Our tent breathable covers come with drawcords. So you can automatically adjust the size of the opening as needed so it doesn't fall over the vents and keep your plant tent clean and dust free. Fine Mesh: The planting shed ventilation filter cover adopts fine mesh, which does not hinder the ventilation of the planting shed. It also effectively keeps dust and small objects out, helping your plants grow healthily. What You Will Receive: We provide 2 duct filter covers, each made of high quality material for your long term use. Two piece combination for easy replacement and cleaning. Easy to Use: Just cover the product over the opening of the ventilation duct, then press the fixing buckle tightly, adjust the elastic cord to a suitable size, and then loosen it to fix it. Also, it can be washed by hand or by machine. Specification: Material: Polyester Size Chart: 4inch: 10cmx7.8cm/3.94inchx3.07inch 6inch: 15.24cmx7.8cm/6.00inchx3.07inch 8inch: 20.32cmx7.8cm/8.00inchx3.07inch Package Includes: 2 Pieces Tent Vent Cover Note: 1. Please allow slightly error due to manual measurement. 2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. 3. Wish you a wonderful online shopping!