For 8 1/2" roller cone bits, everyone has different special concerns about it, and what we do is to maximize the product requirements of each customer, so the quality of our 8 1/2" roller cone bits has been well received by many customers and enjoyed a good reputation in many countries. Roschen Group Limited.8 1/2" roller cone bits have characteristic design & practical performance & competitive price, for more information on the 8 1/2" roller cone bits, please feel free to contact us.
