5/8" OD x 50' Yellow Polythylene Jacketed Copper Tubing for Natural or LP Gas Service Flexible yellow polyethylene-coated copper tubing that is continuously line-marked for clearer identification and protection of natural gas and liquefied petroleum gas installations The polyethylene coating provides added corrosion protection and enables the tubing to be used for both above and below ground installations The continuous line markings on the coating indicates tube contents, ASTM specification, size and lot number which enable the tubing to be traced Polyethylene coating protects copper from corrosion, polyethylene is one of the most inert plastics available Can be used for both above and below ground