Hewai PE-Rt Pipes with Oxygen Barrier for Underfloor Heating ISO Certified. 50-Year Warranty: Comprehensive warranty coverage for 50 years on all products. Oxygen Barrier Technology: EVOH layer prevents oxygen ingress, corrosion, and microbial growth. High Daily Output: Advanced production lines capable of 300,000 meters per day. Premium Raw Materials: Sourced from top global suppliers like Dow, Mitsui, and LG. Full System Guarantee: In-house production of pipes and fittings ensures complete system integrity. Strict Quality Control: 100% visual and functional inspection on all finished products. Customization Available: Flexible customization options for sizes and designs upon request. ISO Certified: Manufacturing processes and products meet international ISO standards.