The Edge Duraboard File is made from Silicon Carbide. It is coarse grit. This black washable, cushioned nail file is specially designed for professionals or home use. This extra cushioned nail file provides for a better grip, ease of use and allows for more control and faster refinement. Product Features Shapes enhanced nails Quickly smooths seams & reduces edges on acrylic nails & tips Washable & Disinfectable Size: 7″ x ¾″ Durable & long lasting Made in UK Standard black washable nail files are manufactured using top quality standard grade sandpaper while the premium nail files are manufactured with the finest abrasive paper sourced from around the world to produce the highest quality and longest lasting nail file. Both standard and premium black nail files are completely water resistant (up to 10 minutes of immersion) and will not swell, shred or peel apart. Nails should always be filed when dry to insure smooth edges. Place the nail file under the nail edge and file in one direction only. 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.