Diamond needle files are used in applications where the surface finish takes priority over fast stock removal rates and are most suited for smaller workpieces.They are often used by engineers and model makers where precision is required.Each set contains six files fitted with comfortable soft-grip handles, the files have a working length of 50mm, blade length of 100mm and an overall length of 150mm. Diamond files are suitable for use on metal and plastic. Six different file profiles as follows: Half round, round, flat taper, square, flat, three square.