API 5CT coupling: 1,API 5 CT 2,O.D:2-3/8" ~20" 3,Grade:J55/K55,N80,P110 ect 4,Thread: ... NU,EU,STC,LTC,BTC API 5CT coupling Feature:1,We ... things as the requirment of our customer.specification:1,Outer diameter: 2-3/8" to 20"2,Grade:J55,K55,N80,L80 ... ,C90,T95,P1103,Type of thread :STC, LTC,BTC4,Standard : API 5CT, API 5B API 5CT Coupling