... 4, (2) Length:3,4,6,7,1 Air Conditioner tube(1)Copper tube:OD:1/4,&3/8,&1/2,&5/8 ... ; reliable, comprehensive specifications. Copper-aluminum connecting pipe in air conditioning manufacturing, air conditioning maintenance is the application.A long life: the ... is needed to connect pipe insulation, and to improve the air conditioner's energy efficiency, should further improve the connection pipe insulation ...