Pentair WC9-3 Black O-Ring Replacement for Select Sta-Rite Pool and Spa Cartridge Filters<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>O-ring replacement</li><li>Fits Sta-Rite Posi-Flo II pool and spa cartridge filters model PTM50， PTM70， PTM100 and compatible with PTM135 Series</li><li>Also fits Sta-Rite pool and spa filters separation tank assembly</li><li>Available in black color</li></ul></div><img src="http://ecx.images-amazon.com/images/I/31A73CwnFGL.jpg" noproxy>