Compulabel # 530807 Rolls Per Carton: 12 Labels Per Roll: 350 Labels Per Carton: 4200 Direct thermal technology does not require a ribbon. Instead a chemically coated heat-sensitive material produces images as heat is applied to the surface. Ideal for indoor applications where temperatures will not exceed high levels.Our thermal rolls are the made from the highest quality materials to ensure proper imaging and processing. Our thermal rolls feature clean release cores. Clean release rolls use all the labels and provides for no jams at the end of the roll. Direct thermal technology does not require a ribbon. Instead a chemically coated heat-sensitive material produces images as heat is applied to the surface. Thermal products are sorted by repeat depth. Pinfeed are also sorted this way. The repeat depth is the depth of a single label plus the gap between itto the next label.Did you know... If youÆre not sure if a label is direct thermal or thermal transfer try the scratch test.ö First lay the label on a hard surface such as a desktop. Next run your fingernail or a pen cap quickly back and forth across the label. If it turns black itÆs a direct thermal label. If not itÆs a thermal transfer label.