Air Conditioner tube 1)Copper tube:OD:1/4,&3/8,& ... 8,&3/4, (2) Length:3,4,6,7,1 Air Conditioner tube(1)Copper tube:OD:1/4,&3/8,&1 ... is needed to connect pipe insulation, and to improve the air conditioner's energy efficiency, should further improve the connection pipe insulation ... connecting pipe copper tube design is 1.5 times the wall thickness, not only to ensure strength and relative connecting copper ...