This item may require additional time for delivery. There are 2 types of HDPE pipe. Inside control diameter (ASTM D2239) and Outside control diameter (ASTM D-3035). We supply Outside control diameter and Philmac fittings are made for the outside control diameter pipe. HIGH PERFORMANCE Made from advanced thermoplastic materials: 3G ID Series compression fittings are manufactured from lightweight high performance thermoplastic materials which, unlike metal fittings, resist corrosion, therefore significantly minimizing maintenance, repairs, and long-term costs. The materials are non-toxic and taint-free and also offer outstanding impact, UV, and chemical resistance. Rated to 230psi: 3G compression fittings are pressure rated to 230 psi to meet the need of the high pressure systems. 50 Year+ Design Life: Built to withstand the toughest conditions to ensure longevity and durability, 3G compression fittings have a 50 year+ design life.