For mix and to moisturize the raw materials, there are two different models: the vertical grits mixer and the horizontal ribbon mixer. Most sold and easiest to use is the vertical grits mixer. Raw materials is feed from floor level and a screw bring the raw materials into the mixer. Water is added and the mix is prepared. Together with the screw feeder (transport to extruder) and extruder hopper it forms one big buffer of raw materials.