The IRWIN® STRAIT-LINE® chalk range has a wide range of permanencies and colors. Whether indoors or out, on finished surfaces, or in extreme conditions, IRWIN® STRAIT-LINE® has the ideal chalk for every job. Dust-off chalk is temporary chalk that can be used to mark interior walls and trim and then be wiped away cleanly. Permanent staining chalk is great for extreme outdoor conditions because it can withstand harsh weather conditions and months of job site wear.