Irwin Strait-Line Red Lumber Crayon is a durable marking tool designed for a variety of surfaces. Measuring 4-1/2 inches, this crayon features a tough compound that ensures waterproof markings and long-lasting use. It performs well on oily, slick, wet, cold, or dry surfaces, making it i for marking wood, concrete, metal, rubber, plastic, cardboard, and ceramic. The wax-based formula is also nontoxic, providing a safe option for everyday use. Model Number: 66401ZR