Industrial Permanent Marker, Fine Bullet Tip, Black, DozenMarkers feature durable permanent inks that resist fading when put to commercial use. The ink is suited for industrial applications, including extreme heat (up to 500 degrees Fahrenheit). These permanent markers can be used on most materials including metal, glass, plastic, film, and foil. Quick drying permanent marker for industrial and laboratory uses. Holds up to extreme heat (up to 500 degrees Fahrenheit). Water , fade and smear resistant. Writes