Pentair U9-229Z - O-Ring 5 in.The Pentair U9 229Z O Ring 5 in. is a trap lid gasket o ring replacement to ensure that there is a proper seal on pool pumps trap covers. Without a quality O Ring pool pumps cannot properly circulate water through pool plumbing systems. Whenever the O Ring start to stretch or tear is suggested that it be replaced to ensure a quality seal. Compatible With: Hayward Sta Rite Dura Glas Hayward Sta Rite Max E Glas JWP and JWPA Pool Pumps