we are china large exporter for the oil pipe and oil equipment We mainly act as Agent for many steel mill and oil feild equipment producer here in china Our export materials drill pipe, drill collar, drill bit, kelly , HW-drill pipe , casing , tubing line pipe ,All above materials, we could submit the API and ISO certificate if you want to buy any above mentioned materials , please contact with us for us very more details sumit you the informations , we could offer you the compective price and Fast delivery times