Boiler makers chalk is a traditional marking tool used by welders, fabricators, and engineers to mark cut lines, centre points, and reference marks on metal surfaces before cutting or assembly. This bulk box contains 144 individual chalk sticks (3.10kg total) with excellent visibility on dark steel and a clean, quick-drying formula that doesn't smudge easily. Ideal for trade workshops, fabrication shops, and on-site construction work where high-volume marking is required.