Irwin Strait-Line Blue Standard Chalk Line Chalk, 5 lb. is designed for use with reel type chalk line boxes, making it an essential tool for both interior and exterior projects. This chalk is packaged in convenient plastic squeeze bottles with a fast fill spout, allowing for easy and efficient refilling. It works effectively on a wide range of surfaces including wood, drywall, concrete, stone, and metal. The marks it leaves are temporary yet provide excellent visibility, ensuring precision in your work. This blue chalk is part of the Blues color family and comes in a 5-pound bottle, for various marking needs without fading quickly. Model Number: 65101ZR