Unlike cardboard wrapped markers, a RotaStik's plastic container stays intact, has a snap-on lid, and a twist out design. So your hands stay clean. Can be safely carried in your pocket. Won't dry out, break up or melt in hot weather. Wax-based RotaStik marks last much longer (3 - 4 weeks) than chalk. Marks are scourable from wool by woolen mills but not by hand washing.