The Silicone Appli-Fuse Mat is made of a silicone and glass fiber material that is heat resistant up to 500 degrees F (260 degrees C). It is the ideal surface for all of your fusing and ironing needs. The mat can be cleaned with soap and water or placed on the top rack of the dishwasher. Measuring 12" X 12", appliqué projects will come together in a snap! Simply place the appliqu design under the Appli-Fuse mat. Multiple layers can be placed simultaneously and pressed with a hot iron. The transparent mat allows you to see and place pieces perfectly. The mat's slight tackiness will keep pieces from shifting when placed.