Made in an aerosol spray form, the Rust-Oleum ChalkBoard spray is easy to apply. It can sprayed on many surfaces such as wood, hardboard, glass or paperboard. Once applied, it take 20 minutes to dry. However, it should be left for 24 hours before chalk can be applied. 1. Elegant and smooth finish 2. Scratch resistant 3.Indoor use only 4. Soap and water clean up 5. Coverage area: 12 square ft