Product Description This IRWIN STRAIT-LINE Permanent Marking Chalk is designed for exterior use. The marks are visible after weeks of weather exposure and jobsite wear. From the Manufacturer The 65202 Strait-Line 2.5lb Red Chalk is what you need to help get things Strait. The Strait-Line 2.5lb red chalk is great for outdoor use, carpentry, bricklaying, masonary, roofing,carpet installation,floor and wall tiling, painting, decorating and many other uses. The red chalk is a permanent chalk which is great for withstanding the wear and tear of the outdoor environment. For more than 30 years, Strait-Line products have represented the standard for excellence and performance in marking tools. Marking chalk is ideal for exterior use Marks are permanent Visible after weeks of weather exposure and jobsite wear Color: Red