Twin/pair insulated copper tube/pipe Our product have got the CE certificate and pass the SGS test! 1,Copper tube:O.D.1 ... 3/8''&3/4'',1/2''&3/4''2,Copper tube:thickness from 0.5mm to 1.5mm.3,Length: ... complied: GB/17791--1999,JISH3300,ASTM B7435,Thickness of copper tube compatible any gases:R22,R407C,R410A,R404A,R507C etc ... absorption9,Insulation pipe can be printed with letter. insulated copper tube kit