PACKAGE & SPECIFICATIONS: Contains 20 1mm drill bits (0.04in head diameter) with 1.4in total length. Features 0.6mm/0.02in shank diameter and 4g lightweight design
CONSTRUCTION: Drill bits for glass is made with powder coating, which has long service life
DRILL BITS FOR STONE: Designed for use with drilling machines requiring 20000 RPM (36mm/1.4in length). Optimal performance achieved when used with cold water cooling system
DRILLING PERFORMANCE: Tipped drill bit is engineered for jewelry, ceramic, jade, agate, glass, amber and semiconductor materials, etc
NOTE: If you use the drill bits for many times, you could cut a little the top of it with plier
