100 Chemex filters Chemex filters are very unique. About 20% - 30% thicker than usual filters and using a fiber design, coffee flow is slowed through the filter itself, trapping more of the oils and solids than thinner filters. The resulting brew is uniquely clean and crisp. Chemex makes unfolded and prefolded filters. These are prefolded for convenience. Will fit all Chemex brewers except CM-1, CM-1C, CM-1GH