Proper Size - The disc coffee filter measures 3.75 inches and the diameter of the center hole is 0.39 inches, which are the standard size in the market. It's suitable for banquets, parties , restaurants and homes, etc. Premium Material - Our coffee filters are made of premium paper, with superior air permeability, strength and water permeability and firmness, helping you make delicious coffee. Economical - If you really enjoy brewing your own coffee at home, our 300-piece filter paper is a great option that will take less time and money than going to a coffee shop. At home you can enjoy delicious coffee anytime, anywhere, just from the comfort of your home! Function - The round coffee filter can filter out the particles in the ground coffee to form a pure coffee solution, and filter out other impurities at the same time, allowing you to taste the original coffee. Wide Applications - These unbleached coffee filters are not limited to percolators only. They can also be applied in various other coffee brewing methods such as French press, pour over, or even as loose tea filters. The versatility of these filters ensures that you can enjoy a cup of coffee no matter how you choose to brew it, suitable for coffee shop, home, office and so on.