The Staleks Half Moon Mineral Nail File Expert 40 80/100 Grit (NFE-40-80/100) is a half-moon file with 80 grit on one side and 100 grit on the other. 80 grit is the coarsest grit, making it easy to file through strong nail product or to thin out a large amount of nail product. 100 grit is a coarse grit, allowing you to easily file artificial nails into length and shape. 80/100 grit is perfect for filing strong or thick artificial nails, acrylic nails, acrygel nails, or hard gel nails. The shape of this file is a half moon, with a curved side and a straight side, an all-rounder! With the curved side, you can easily file along the cuticles or file any file line. The straight side is perfect for shaping the free edge of the nail or for perfecting the top of the nail plate. You can also use the straight side to carefully correct the shape of natural nails and artificial nails without damaging the nail plate or leaving tiny cracks. This Staleks half moon file has several high-quality features. The special coating on the mineral nail file prevents clogging of the abrasive paper by filing dust; the file is made of a flexible plastic base with a thin layer of foam that reduces pressure on the nail plate.