Irwin STRAIT-LINE marking chalks have a newly engineered flip-top cap that keeps the chalk in the bottle where you want it and stops it from spilling out in areas that you don’t. The flip-top cap, available on all Irwin STRAIT-LINE chalk bottles, seals the chalk in an air-tight chamber, keeping out moisture and reducing the risk of clumping.

• Exterior use
• V-jaws give you more points of contact on round stock and tubing