These cost-effective, easy-to-use temperature-indicating crayon sticks provide fast, accurate surface temperature measurements for a wide range of applications. The sticks are available in temperature ratings from 100 to 650⁰F (38 to 343⁰C) with a NIST-traceable accuracy of ±1%. Simply apply to heated surface-crayon melts instantly at designated temperature leaving a distinct mark for easy and immediate visual inspection. Featuring a unique slip-resistant aluminum holder, the crayons can be used on steel, iron, aluminum, stainless steel, glass, plastic, and ceramic surfaces in a variety of industries. Part number, temperature and lot code are imprinted across entire crayon stick. Crayons exceed industry standards delivering products free of sulfur, lead, and halogen contaminants. Inexpensive alternative for surface temperature measurement Calibration free with 100% temperature reliability. Comply with AWS, ASME, and ANSI/ASME preheat temperature requirements