Interlock knit is a double knit fabric. It’s a variation of a rib knit and it’s similar to jersey knit, but it’s thicker; in fact, interlock knit is like two pieces of jersey knit attached back to back with the same thread. As a result, it has a lot more stretch than jersey knit; additionally, it looks the same on both sides of the material because the yarn drawn through the center, between the two sides. In addition to having more stretch than jersey knit and having the same appearance on both the front and back of the material, it’s also thicker than jersey; plus, it doesn’t curl. Interlock knit is the tightest of all knit fabrics. As such, it has the finest hand and the smoothest surface of all knits.