Diamond Nail Drill Bits D-16, shape rounded cone, head size 2.1x10 mm This popular shape Rounded Cone is used for manicures and pedicures. These bits are of three variants. Fine (red) bits are recommended for: Polishing the cuticle zone after removing the cuticle; Cleaning under the nail edge. Medium (blue) bits are recommended for: Lifting the cuticles before strengthening the nail plate bio gel or applying acrylic to the nail plate; Cleaning the nail wall; Removing dry, dead cuticles. Coarse (green) recommended for: Removing rough, dry, dead cuticles around the nail and wall nail; Cleaning rough, dry the nail wall; Specifications: Speed recommendation: Up to 25000 RPM. Shank diameter: 3/32” Head dimensions: 2.1x10mm Length: 45mm Grit: Fine, Medium, Coarse Shape: Rounded Cone Material head: Diamond Material shank: Stainless steel