We pursue the administration tenet of Quality is remarkable, Services is supreme, Status is first, and will sincerely create and share success with all customers for 311mm well drilling head, single roller cone bit, 311mm IADC517 drill bit, cone bits IADC517 11 5/8 inches drill bit,well drilling pdc bit. Living by good quality, enhancement by credit history is our eternal pursuit, We firmly feel that soon after your visit we will become long-term associates. The product will supply to all over the world, such as Europe, America, Australia,Iraq, Honduras,Malaysia, Sheffield.Excellent quality, competitive price, punctual delivery and dependable service can be guaranteed. For further inquires please do not hesitate to contact us. Thank you - Your support continuously inspires us.