It consists of positioning elements, clamping devices, tool setting devices, guiding elements or devices, connecting elements, clamping bodies and other elements and devices.

Hazelnut: It is one of the important nut tree species, and it is a woody oil tree species, belonging to the genus Corylus of Corylaceae. There are 16 species in the world, mainly distributed in Asia, Europe and North America. The fruit is chestnut-shaped, ovoid and has a yellowish brown shell. The seeds are fragrant, sweet and oily, and harvested in autumn. The shell of hazelnut is hard, but hazelnut has a special clip, which is very convenient to eat.