It is a string of artificial and chemical fibers. This thread is not used in handmade rugs because it lacks the appropriateness and features, including synthetic threads, it can be pointed out to the following: A-Rayon: it is from cellulose fibers and in this regard it is very similar to silk, and is known as “artificial root” and silk, which is composed of protein resistance. (b) Visco Riven: This is especially broken against moisture and has no resistance.