... a high pressure plastic pipe system. Reinforced Thermoplastic Pipe (RTP)Products structure:RTP(Reinforced Thermoplastic Pipe) is a high pressure plastic pipe ... liners are made of PE80 or above, and the middle liner is made of reinforcement tape. You could choose a special ... ): 2.5, 4, 4.5, 5, 5.5, 6 Reinforced Thermoplastic Pipe (RTP)