A kief press is a small, manual device that lets you press kief - the pollen that accumulates at the bottom of the grinder featured with a special screen. It can also be separated from herbs with the use of a fine screen. Kief consists mainly of trichomes - the parts of the plant that contain the highest concentration of the active substances. Pressed kief can be crushed and mixed with the herbs you put into a vaporizer, which will guarantee much stronger results. The best quality kief (extracted with the use of a very fine screen) is almost entirely free of plant material so it can be used in the devices designed for concentrates vaporization. Pressed kief can be turned into rosin - a type of concentrate. If you collect kief - either in a grinder or using other methods - a kief press is a must-have!