Pleatco PSR50-4 Sta-Rite Posi-Flo 50GPM-TX， 50TX， 50TXR， T-50TX， T-50TXR， II PTM50， Open with 12 Concentric Slots， 1 Cartridge<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Replacement filter for pool and spa cleaning systems</li><li>50% open ABS free flow cores maximize water flow through REEMAY filter media</li><li>Antimicrobial end caps resist chlorine degradation and provide support to filter material for a longer life span</li><li>13-5/16-by-4-3/16-by-4-3/16-inches</li><li>Made in the USA</li></ul></div><img src="http://ecx.images-amazon.com/images/I/51JldDxQN8L.jpg" noproxy>