The file surface is a special procedure that applies semiconductor technology. easily and Quickly polish lustrous nails in one step. Smoothly correct nail length and shape. We continue luster of nail for approximately two weeks after polishing. How to use: Apply a file on the nail and file it in a particular direction to lessen the length as well as shape. Apply the file surface on the surface area of the nail and run it lightly to finish the area with luster. After use, wash and drain, and dry very well before storing in case.