{"product_id":"back-up-ring-ss","title":"Pentair Genuine OEM Back-Up Ring, Stainless Steel","description":"\u003cp\u003eThe Pentair 195339 is a stainless steel back-up ring, a small metal part with one job: to sit behind an o-ring so the seal cannot be forced out of its groove when the filter comes up to pressure.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy filters use them\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eAn o-ring on its own can extrude through a gap under enough pressure, and once it has been pinched or nibbled it will never seal properly again. The rigid back-up ring closes off that escape path. It is one of those parts that goes unnoticed until it is missing or distorted, at which point the filter starts weeping at a joint that keeps failing no matter how many new o-rings go in.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eBefore you order\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe Pentair sources list this part in more than one place: it appears in the PacFab FNS Plus DE and Quad DE parts diagrams, and it is also grouped with Clean and Clear Plus cartridge filter parts. Check it against the exploded view for your own filter, and plan on fitting a new o-ring at the same time.\u003c\/p\u003e","brand":"Pentair","offers":[{"title":"Default Title","offer_id":48628943749332,"sku":"PAC-051-101","price":77.66,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0801\/9568\/2516\/files\/default_3b755fa4-6daa-46d9-84a2-8b466225631c.png?v=1788758336","url":"https:\/\/www.activepoolsupply.com\/products\/back-up-ring-ss","provider":"Active Pool Supply","version":"1.0","type":"link"}