OLFA Professional Self-Healing Rotary Mats extend the life of rotary blades and protects cutting surfaces. 1.6mm thick double-sided triple layer mats with a dark green base colour and yellow grid lines on one side and solid green on the reverse. OLFA’s patented "self-healing" mats are designed to take the wear and tear that your rotary cutting blades dish out. "Self-healing" means that the mat will not get cuts, grooves, or nicks on its surface over a normal wear and tear lifecycle, all of which can make your cutting less than perfect. It provides a continually smooth surface for all cutting projects Stays clean too with no rough surface to catch dirt and fabric dust. Do not iron on mat, store flat, do not roll. keep out of direct sunlight, avoid extreme hot or cold to prevent warping. For use only with rotary blades, fixed-blade knives may damage mat.