The different colors help distinguish the different uses of buffer blocks for acrylic nails for polishing glossy nails, crystal nails and patch nails. The different grit of the nail buffing blocks bulk help you create nails of any shape and length. Nail buffer sanding block bulk is small and cute, easy to carry and polish onto your nails anytime and anywhere. High-density sponge makes you feel more comfortable and nail buffer blocks won't hurt your skin when sanding,It is a common tool for nail salon to polish nail surface. 20 Pieces of nail sanding buffing block made of high quality sandpaper, durable and washable, easy to sand and polish.