The 65105 Strait-Line 5lb Fluorescent Orange Chalk is what you need to help get things Strait. The Strait-Line chalk is great for outdoor use, carpentry, bricklaying, masonary, roofing,carpet installation,floor and wall tiling, painting, decorating and many other uses. Fluorescent orange is permanent color that will endure the wear and tear of the outside environment For more than 30 years, Strait-Line products have represented the standard for excellence and performance in marking tools.