Air Conditioner tube 1)Copper tube:OD:1/4,&3/8,&1/ ... /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 ... copper pipe is easier to install and transfer machines. copper-aluminum tube & Air Conditioner tube