Permanent markers feature a bold, low-odor ink that provides high visibility from a distance on most surfaces, including cardboard, metal and plastic. Generous supply of low-odor, quick-drying, nontoxic, water-resistant and rub-resistant ink. Markers work well both indoors or out. Durable, 3/16" chisel tip writes in a variety of line widths. ACMI certified ink conforms to ASTM D-4236.