Glass Nail File
Ultra performing super resistant, extremely precise, it can be also used on artificial nails. It is more delicate than emery board or steel ones, it is less aggressive because it is not porous. Recommended for those who have brittle, peeling nails. Glass does not heat the nail up and avoids micro chipping. One other positive thing about this file is hygiene, as it can be washed with water or even sanitized.
Remember to file nails always in the same direction, you should avoid going back and forth in order to prevent flaking.