Two-Ply Shirt: Two-ply is a way of weaving cotton. Two-Ply, double twisted or Two-Fold fabrics feel tighter and more compact. 2 threads are woven together into 1 thread. Two-Ply is also called Doppio Rittorto in Italian. 2Ply or 2Fold shirts are sturdy and sustainable. Most common are two-ply yarns, formed by twisting two single yarns together. The plying twist is in the opposite direction of the singles twist. That means most ply yarns will contain an “S” twist. Ply yarns are used where extra strength and evenness are required.