... ,K55,N80,L80,C90,P110, N80-1,N80-Q Type: NU, EU Coupling Manufacturer of Tubing and Casing ... -1/2"EUE141.30*158.756.051.Grade:J55, K55, N80-1, N80-Q, L80, C90, P110 ... 4.Type: NU, EU(tubing coupling), STC,LC,BTC(casing coupling). 5.Surface treatment: Whole phosphating, or inside ... by requirements of customers Our company manufacture and sell casing and tubing couplings,pup joints, tool joints, adapter ...