{"product_id":"value-collection-zmschb90334-o-ring-backup-ring-nbr-90d","title":"Value Collection ZMSCHB90334 O-ring Backup Ring Nbr 90D","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe VALUE COLLECTION ZMSCHB90334 is a rectangular cross-section backup O-ring designed to prevent extrusion in high-pressure sealing applications. Manufactured from Nitrile Butadiene Rubber (NBR) with a 90 durometer hardness rating classified as extra hard, this ring measures 2.643 inches inner diameter by 3.009 inches outer diameter with a 0.0625-inch thickness. The 90 durometer compound resists deformation under load, making it well suited for hydraulic, pneumatic, and fluid system assemblies where standard O-rings require anti-extrusion support. Plumbers, HVAC technicians, and industrial maintenance professionals install backup rings alongside primary O-ring seals in grooved fittings and cylinder bores.\u003c\/p\u003e\u003cp\u003eThis backup ring is used in residential and commercial fluid systems where elevated pressure or temperature cycling would otherwise allow a primary O-ring to extrude past a clearance gap. The Dash 8-334 designation identifies the ring geometry within the standard sizing system, simplifying cross-reference and replacement sourcing. Typical installation scenarios include hydraulic cylinder rod seals, manifold face seals, and threaded port connections in plumbing and HVAC equipment exposed to a working temperature range of -40 to 250 degrees F. Sold in a package quantity of 10.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003eRectangular cross-section profile functions as an anti-extrusion backup ring alongside primary O-ring seals\u003c\/li\u003e\n\u003cli\u003eNBR compound rated extra hard at 90 durometer for high-pressure resistance\u003c\/li\u003e\n\u003cli\u003eWorking temperature range of -40 to 250 degrees F suits refrigerant, water, and hydraulic fluid service\u003c\/li\u003e\n\u003cli\u003eDash 8-334 standard designation allows straightforward cross-reference and replacement identification\u003c\/li\u003e\n\u003cli\u003ePackage quantity of 10 supports stocking for repeat service calls\u003c\/li\u003e\n\u003cli\u003eWeighs 0.02 pounds per unit; minimal bulk for field carry\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned as an OEM-style replacement backup ring for fluid system assemblies requiring a Dash 8-334 rectangular cross-section seal with a 2.643-inch inner diameter and 3.009-inch outer diameter.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eInstallation is performed by licensed plumbers, HVAC technicians, or qualified industrial maintenance personnel. Always depressurize and de-energize the system and drain fluid from the assembly before removing or installing seals. Backup rings are typically seated in the groove behind the primary O-ring on the low-pressure side; verify groove dimensions match the ring cross-section before assembly. Do not twist or stretch the ring during installation, as permanent deformation will compromise the seal.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: Nitrile Butadiene Rubber (NBR)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDash Number\u003c\/strong\u003e: 8-334\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInside Diameter\u003c\/strong\u003e: 2.643 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOutside Diameter\u003c\/strong\u003e: 3.009 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThickness\u003c\/strong\u003e: 0.0625 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCross Section Shape\u003c\/strong\u003e: Rectangle\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHardness\u003c\/strong\u003e: 90 Durometer (Extra Hard)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMinimum Working Temperature\u003c\/strong\u003e: -40 degrees F\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaximum Working Temperature\u003c\/strong\u003e: 250 degrees F\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFDA Approved\u003c\/strong\u003e: No\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePackage Quantity\u003c\/strong\u003e: 10\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 0.02 pounds\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eStandard Information\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: VALUE COLLECTION\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: ZMSCHB90334\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"VALUE COLLECTION","offers":[{"title":"Default Title","offer_id":51692805620018,"sku":"ZMSCHB90334","price":14.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/bbbcceebcc98f31c0d76bce29370f44a_fc13a767-c146-4078-99f7-21a1ae2f553f.jpg?v=1788303186","url":"https:\/\/voomisupply.com\/products\/value-collection-zmschb90334-o-ring-backup-ring-nbr-90d","provider":"Voomi Supply","version":"1.0","type":"link"}