The Staleks Half Moon Mineral File Expert 40 100/150 Grit (NFE-40-100/150) is a half-moon file with 100 grit on one side and 150 grit on the other. 100 grit is a coarse strength, perfect for easily filing artificial nails into shape and length. 150 grit is a medium-coarse strength, suitable for filing artificial nails, gel nails, BIAB nails, or natural nails. The shape of this file is a half-moon, with a curved side and a straight side, making it an all-rounder! The curved side allows you to easily file along the cuticles or any file line. The straight side is perfect for shaping the free edge of the nail or refining the top surface of the nail plate. You can also use the straight side to carefully correct the shape of natural 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 in the abrasive paper from filing dust, and the file is made of a flexible plastic base with a thin layer of foam that reduces pressure on the nail plate.