AWWA C903:2005 Polyethylene-Aluminum-Polyethylene And Cross-Linked Polyethylene-Aluminum-Cross-Linked Polyethylene Composite Pressure Pipes, 1/2 In. (12 Mm) Through 2 In. (50 Mm), For Water Service Specifies coextruded polyethylene (PE) composite pressure pipes with a welded aluminum tube reinforcement between the inner and outer layers of PE, primarily for use as underground water service lines