There are two advantages to using a stainless steel coffee filter: (a) it's reusable; and, (b) it allows more of the oils from your brewed coffee to find their way into your cup. The Kone coffee filter fits 6-, 8-, and 10-cup Chemex coffee makers. It was designed by Coava (pronounced ko-vuh) Coffee Roasters in Portland, Oregon, and seeks to save you from throwing away paper filters every day.