Engineered for tradesmen, the 1/4 in. x 8 in. x 12 in. Rotary Percussion Drill Bit has a copper braze material for a high heat resistance. This bit is made for hammer drills with a 3-jaw or Jacobs chuck, with a shaft made of chrome-vanadium spring steel for added strength. Bit removes dust fast with a double-ground, extra-deep flute for increased speed and better bit life.