LegendFlex™ Highly flexible PEX heating tube with oxygen barrier is manufactured from a proprietary polymer formulation which dramatically increases flexibility and maintains high strength. Available in 3/8 in, 1/2 in, 5/8 in, 3/4 in and 1in tube sizes. LegendFlex™ delivers greater performance and flexibility than standard PEX. We are so confident in its performance we back it with a 30 year warranty. Kinks are repairable with a heat gun. LegendFlex tubing is compatible with cold expansion type fitting systems (compliant with standards ASTM F2080 & ASTM F1960). Its strength, durability and thermal memory enables proper seal with crimp or expansion style connections.