The pattern and material of the plate has a close relationship with not only pulp quality but also available feed amount of chip and specific power consumption. The pattern and material are selected based on experience and operation record. The plate is composed of two sections: breaking zone where chips are roughly broken, and refining zone for complete defibration and beating. The plate is made of high-chrome stainless steel. One set includes six plates. Three plates on each side (rotational and fixed sides) forms one segment. The photo shows the shapes.