Filter for extraction device

A method and device for preparing an extract with a froth layer, provided with a holder which during use includes a lower filter and an upper filter, each consisting of an outer edge of washable, sturdy material, which fit onto each other, and an inner part of washable material with small holes, and wherein the substance to be extracted is received between the lower filter and the upper filter. A lower filter or upper filter for use in such a device is also disclosed.