... High efficiency and high quality. Huazuan drill bit for concrete,refractory bricks, asphalt Description:Used for wet cutting building materials such as ... concrete, bricks, granite, marble, stone,cements, etc.Specification: Diameter (D)Max ... 86780371Fax:0086-595-86780372 Certification: Huazuan drill bit for concrete,refractory bricks, asphalt