Each reusable coffee filter is made with 100% GOTS certified organic cotton muslin and is serged for a professional and durable finish. The same filter can be used for years to come; just rinse and reuse. A wonderful swap for a sustainable home. TYPE + QUANTITY Our reusable coffee filter is technically a cone-shaped filter and sits easily in cone or basket coffee makers, is perfect for machine or pour-over coffee, and is easy to remove and care for. I prefer this over a circular style typically used for baskets, which is a bit messier to get out. The filter is based on Size #4, which fits 8-12 cup makers. However, the cloth easily folds down to accommodate a variety of sizes. CARE INSTRUCTIONS Boil water and place your filter(s) in before the first use to sterilize and reduce any foreign fibers from the sewing process. Hang dry, and you're ready to brew! No need to boil between every use (a good, warm rinse will do the trick!).