MusicNomad Diamond Coated Nut File .017" / 0.43 mm, nut file with industrial strength diamond coating, diameter: .017" / 0.43 mm, grit: 150, 44 mm (1.75") cutting surface, innovative, round 'string-shape' blade design for smooth, precise cuts, laser engraved size on the blade, ergonomic handle and convenient workbench hang hole, perfect for cutting and polishing at the same time for new or existing nut slots, great for the most common nut materials (nylon, bone, graphite, TUSQ) and even works amazing on saddles Note: Used properly, the MusicNomad saddle file with diamond coating will last a very long time. Originally known from industrial applications, diamond is considered one of the most durable abrasives available. Use these files only for nuts made of bone, graphite, nylon or TUSQ materials, or for saddles made from brass or zinc. The files are not suitable for cutting steel. Clean the files regularly with a brush to remove grinding debris from the gaps in the diamond coating. Should the grinding action on the front part of the file wear off, the file can be rotated in the handle to bring the less-used rear part to the front.