Made of high-tech , 3-ply polymer, Blick Self-Healing Cutting Mats have a self-healing surface that holds up under repeated use. They are available in four sizes and two color options — double-sided Black/Gray or Translucent. Calibrated inch grid lines make cutting easy. Two 45° angled lines and one 60° angled line are helpful for making diagonal cuts. If your Blick Cutting Mat should become bent or distorted, simply heat it in sunlight or hot water until it becomes pliable and then lay it flat until cool.