Over the years the Keson formula for ProChalk® has been fine-tuned to produce chalk that performs with consistent excellence, batch after batch. Keson ProChalk® Semi-Permanent Intensity chalk is formulated to meet the diverse needs of customers. The color and amount of the pigment determines the vividness and permanence of the line. The Semi-Permanent Intensity chalk sticks to your line until you decide you want it to stick to something else.

ProChalk® Semi-Permanent Intensity chalk is used for weather and water resistant lines that hit and stick for a long time but will eventually wear away naturally. This chalk is best for exterior applications including concrete layout, roofing, and metal fabrication.