The Zhongruan is made without the use of any plastic or ivory with pegs made out of the same material.
It is usually made of plastic, buffalo bone or ivory. 
The frets are usually made of plastic, buffalo bone, wood and metal (copper). 
For a good quality zhongruan, the frets are made of a combination of plastic and copper, or wood and copper, with the metal part inlaid at the top of each fret. 
