... 5CT, ISO 4.Place of Origin: China Casing Pipe------------------------------------------------------------------------------------------------------------------------ FeaturesMaterials: H-40,J-55,K-55,N-80,C-75 ... of End-finish: Plain, BTC, LTC,STC Grades: H-40, J-55, K-55, N-80, C-75, ... company is specializing in the process of oil casing, tubing, casing coupling, pup joint, reducer union, drill pipe ...