Pentair 35505-1429 O-Ring Replacement for Sta-Rite System 3 Pool and Spa Cartridge Filter<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Elbow assembly O-ring replacement</li><li>Fits Sta-Rite System 3 Modular Media SM series pool and spa cartridge filters model S7M120， S7M400， S8M150， S8M500</li><li>Available in small size</li></ul></div><img src="http://ecx.images-amazon.com/images/I/41RBDr20ulL.jpg" noproxy>