{"product_id":"pentairwaterpoolandspainc_r172374","title":"Pentair Lock Spring | Dynamic Filter Series II \u0026 III | R172374","description":"\u003cp\u003eThe Pentair Lock Spring (R172374) is the OEM replacement lock spring for the Dynamic Filter Series II \u0026amp; III Top Load Inline Cartridge Filter and Automatic Feeders (see model list below).\u003c\/p\u003e\n\u003cp\u003eThe lock spring secures the filter lid or cartridge retainer assembly in the closed position during operation, maintaining the seal integrity of the filter housing under normal operating pressure. A fatigued or broken lock spring will prevent the lid from locking down correctly, resulting in pressure loss or an improperly sealed filter. Replace this spring whenever the lid no longer holds its locked position or when servicing the filter cartridge as part of routine maintenance.\u003c\/p\u003e\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; margin: 20px 0; border: 1px solid #ccc;\"\u003e\n\u003ctbody\u003e\n\u003ctr style=\"background-color: #f8f9fa;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003ePentair Part Number\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eR172374\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eQuantity Included\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eEach\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eFits Into\u003c\/h3\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; margin: 20px 0; border: 1px solid #ccc;\"\u003e\n\u003ctbody\u003e\n\u003ctr style=\"background-color: #f8f9fa;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eBrand\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eEquipment Line\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eModel \/ Part Number\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eNotes\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003ePentair\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eDynamic Filter Series II \u0026amp; III RTL\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eRTL\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eTop Load Inline Cartridge Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f8f9fa;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003ePentair\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eDynamic Filter Series II \u0026amp; III RCF\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eRCF\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eTop Load Inline Cartridge Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003eAlso fits Pentair high capacity automatic feeders models HC-3315, HC-3330, HC-3340 and Dynamic Series V DSC 75 and DSC 100\u003c\/p\u003e\n\u003cp\u003e\u003cem\u003eCompatibility is based on Pentair parts documentation and available OEM records. This is not an exhaustive list. For certainty, verify the part number in your equipment's manual or on the original part itself before ordering.\u003c\/em\u003e\u003c\/p\u003e\n\u003ch3\u003ePro Tip\u003c\/h3\u003e\n\u003cp\u003eBefore ordering, compare the part number stamped or molded on your existing spring against R172374 to confirm fitment.\u003c\/p\u003e\n\u003c!-- wft:processed:manual:2026-04-06 --\u003e","brand":"Pentair","offers":[{"title":"Default Title","offer_id":53971961118995,"sku":"R172374","price":12.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0920\/0687\/5411\/files\/pentair-lock-spring-dynamic-filter-series-ii-iii-r172374.webp?v=1776797947","url":"https:\/\/poolaroo.com\/products\/pentairwaterpoolandspainc_r172374","provider":"Poolaroo","version":"1.0","type":"link"}