The Edge Duraboard 100/180 Grit File (x 10) is combined with both coarse (100) and medium (180) grit. It is a washable, cushioned file providing a better grip, allowing for more control and faster refinement. Cleaning Instructions: Put nail file under running water and brush the grit surfaces lightly. Do not leave immersed under water for more than 10 minutes. Pat dry and allow to air dry for 24 hours before re-use. Also available in singles.