Irwin 65101ZR 5Lb Blue Strait-Line Chalk Refill (4 Pack)

Marking chalk marks are temporary. Provides greater visibility in standard lighting conditions. Durable formula is weather-resistant and suitable for interior or exterior use. Use to show layout changes and corrections on metal, concrete, lumber, plastic, cardboard and other surfaces. IRWIN Tools STRAIT-LINE Standard Marking Chalk, 5-pound, Blue Chalk (65101ZR)