Fun to use on any chalk friendly surface to create murals or sidewalk doodles.  Moon Chalk is made from 100% chalk, easily washes off any surface, is non toxic, and the creators say it will defy gravity if used on the surface of the moon! 
Color Set includes one of each:
Cosmic Pollen in yellow (3" x 3" x 3")
Lunar Rake in blue (3.64" x 2.2" x 2.2")
Satellite Stack in red (2.88" x 3" x 3")