The permanent ink resists wear and water exposure and is perfect for any use. These markers work with multiple surfaces including paper, cardboard, metal, PVC, concrete, plastic and ceramic. Write on sports equipment, make signs for yard sales, mark boxes and more. Marks-A-Lot chisel tip markers are great everywhere from classrooms and offices to warehouses and manufacturing facilities. Avery Marks-A-Lot permanent markers are also low-odor and nontoxic so that they can be safe in classrooms as well as in laboratories. Desk-style permanent markers in this value pack deliver bold, low-odor ink that provides high visibility from a distance on most surfaces including cardboard, metal and plastic. The ink is ACMI certified as nontoxic and conforms to ASTM D4236.