The white paper filters are specially designed to fit the Keeta Wave Coffee Percolator with its flat bottom. Kalita Wave filters are the best in filters you will try and only need to be rinsed slightly before you start filtering. Made from the finest paper and polished to perfection to ensure the quality of high quality beverages, flat bottom paper filters designed for use with the Kalita 155 drip pans or the stylish Keita Wave 25 paper filter