1,Tricone bit,rock bit,three tooth triconebit 2.certified by ISO,API 3.wide size code 4.best price ,delivery on time HeJian ... bit1.High-strength, high flexibility, high temperature, high wear resistance.2. High-precision metal seal.3. Locking roller ball, to adapt ... to high-speed.4. The use of high strength high toughness carbide teeth,5 ...