Note: These bits do not work with the Medicool File Stream, Vac File or Vac or File Classic Vacuum Suction machines. Long Lasting titanium Nitride Coated for adjusting Acrylics and Metals. Silver Carbide Safety Barrel for use with Medicool Files and Drills: Shaft 3/32 Carbide bits are designed for the filing and shaping of acrylic and artificial gel nails. Available in 8 different grits and a variety of shapes and sizes to accommodate the user's preference or filing task.