Twin pencil sharpener to keep both slim & chubby pencils in optimum condition. What it is formulated to do: This must-have tool was specifically designed to fit Endless Silky Eye Pen & Lid Last Shadow Pen, but it also works for most standard size pencils. Blade cleaner included for your convenience. Put pencils in the freezer for a few minutes before sharpening. This will solidify the formula and minimize lead breakage. Use gentle pressure to sharpen - do not press pencil too hard when sharpening.