The 65106 Strait-Line 5lb Fluorescent Green Chalk is what you need to help get things Strait. The Strait-Line chalk is great for outdoor use, carpentry, bricklaying, masonry, roofing,carpet installation,floor and wall tiling, painting, decorating and many other uses. Fluorescent green is a permanent color that you would use if you need for greater visibility on dark surfaces. For more than 30 years, Strait-Line products have represented the standard for excellence and performance in marking tools.