Use the write-on/wipe-off surface to practice writing words, to work on math problems, to label bins, or to jot down reminders or positive affirmations. The spots attach firmly to smooth, untextured surfaces. Remove protective backer before applying to surface. Removable and reusable. Measures 4" diameter. Each pack includes 12 pieces in 6 colors: red, orange, yellow, green, blue, and purple.