For 20''508mm bit, 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 20''508mm bit has been well received by many customers and enjoyed a good reputation in many countries. Hejian Hengji Bit Manufacture Co., Ltd. 20''508mm bit have characteristic design & practical performance & competitive price, for more information on the 20''508mm bit, please feel free to contact us.