The X-5 solid paint marker is recommended where marking temperatures vary rapidly from 150°F to 900°F (66°C to 482°C). This hot surface paint crayon is ideal for very rough surfaces such as open-hearth ingots, forging, hot slabs, and other metals. Dual-purpose paint crayon is ideal for use where temperatures vary rapidly from hot to cold Unique marker is ideal for very rough surfaces like open-hearth ingots, forgings, and rough castings Formulated for foundries and mills where extreme temperature change occurs Durable marks will not run, char, flow, discolor, peel or crack, but can be removed at higher temperatures Marking range: 150°F to 900°F (66°C to 482°C) Made in U.S.A.Sold in a Case of 144