This is our class 4 gas lift,it has passed TUV,SGS,LGA test.The quality of the gas lift is high. This ... is our class 4 gas lift,it has passed TUV,SGS ... ,LGA test.The quality of the gas lift is high.We ... :TUV,SGS,LGAThe thickness of the inside of the gas lift(28pipe):2.5mmThe thickness of the outside of ...