Diamond drill bits D-90 size head 2.1x8 mm Flame is one of the most popular shapes used for both manicure and pedicure procedures. Extra fine bits (yellow) are recommended for: Lifting sensitive cuticles. Polishing the cuticle zone after removing the cuticle. Fine bits (red) are recommended for: Polishing the cuticle zone after removing the cuticle. Medium bits (blue) are recommended for: Lifting the cuticles before strengthening the nail plate with bio gel or applying acrylic to the nail plate. Cleaning the nail wall. Coarse bits (green) are recommended for: Cleaning and shaping nail plates. Lifting and removing rough cuticles. Cleaning nail grooves. Treating hyperkeratosis, small corns, and calluses. Specifications: Speed recommendation: Up to 25000 RPM. Shank diameter: 3/32” Head dimensions: 2.1x8.0mm Bit Shape: Flame