... layer of aluminum, the expansion co-efficient a samll metal pipe with considerable strength, toughness, impact resistance.5 ... conductivity of metal pipes1/200 only, hot water pipe insulation for excellent energy saving effect.8. Light weight, ... , and it will just take a few seconds to complete a joint connections,and metal water pipes ... ,0058P02.75575x7,505 pex multilayer pipe for underfloor heating