Interior use; eliminates need for primer before painting. Cleanly wipes off smooth and rough surfaces. The flip-top cap seals the chalk in an airtight chamber, keeping out moisture and reducing the risk of clumping.
Marked both sides, both edges. Graduated to 1/16ths both edges; 16" stud centers marked in red. Regular outside markings. For rules with inside markings, numbering begins on inside of rule with measurement laying close to work.