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Little did Professor Z. Yao at China University of Geosciences know when he started researching and designing cutting-edge drilling bits in 1986, that he would later turn KingRock into one of the most...

Yichang Shenda Petromachine CO.,LTD. is a manufacturer of diamond bits with well-equipped testing facilities and strong technical force.With a wide range, good quality, reasonable prices and stylish d...

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