Irwin Strait Line 8 oz. Red Powder Chalk in a plastic bottle is used for snap line mark. It is odorless and has a specific gravity of 3.3 to 3.35, a relative density of 3.4 to 3.45, and a pH range of 8.5 to 9.5. 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.

• 8 oz. Red Powder Chalk in a plastic bottle.
• Used for snap line mark.
• Odorless.
• Specific gravity of 3.3 to 3.35.
• Relative density of 3.4 to 3.45.
• pH range of 8.5 to 9.5.