The 3 lb. Blue ProChalk Plus Waterproof Chalk is a premium quality chalk designed for professional use in various industries such as construction and carpentry. This chalk is manufactured using a special formula that makes it resistant to water, thus ensuring that the chalk lines remain visible even in damp conditions. The vibrant blue color of the chalk provides excellent visibility on a variety of surfaces, making it easy for workers to accurately mark measurements and layouts. In addition to its waterproof properties, the 3 lb. Blue ProChalk Plus Waterproof Chalk is also known for its high strength and durability. This chalk is made from fine particles that adhere tightly to the surface, preventing it from wearing off easily. This ensures that the chalk lines remain crisp and clear, even after extended use. Overall, the 3 lb. Blue ProChalk Plus Waterproof Chalk is a reliable and high-performance tool that is essential for professionals who require precision and accuracy in their work. Professional grade marking chalk Water-resistant lines hold your mark 8-10 strikes usual line yield Great flow for easy reel fill-up Brilliant weather-proof color