A ball-shaped rotary file with optimal abrasiveness of 180 grit and diameter (4 mm) for a comfortable treatment of nail cuticles and lateral ridges. - Delicate treatment. Rotary files with optimal abrasiveness and diameter for a comfortable treatment of nail cuticles and lateral ridges. - Durability. Composed of exceptionally high-quality materials – steel, synthetic diamonds, and nickel – to guarantee the rotary files’ long service life. - Hygiene. Rotary files can be disinfected in any solution and sterilized at any temperature.