Sharpen Carbide Nail Bits: Comes with 3pcs tungsten carbide nail drill bits, which are made of optimum strength tungsten carbide material. Sturdy sharpe enough to sharpen acrylic gel nails, thick extension nails, builder gel nails. Professional Cuticle Nail Drill Bits: Comes with 1pcs ball bit and 2pcs flame bits, which are made of premium diamond metal, allowing you to prepare the nail bed, clean the cuticle area, shape and shorten the nail, smoothly remove on the surface, drill nail holes, and so on.