{"product_id":"southwark-metal-21r81420-end-cap-model-21-r8-insulation-14-inches-x-20-inches","title":"Southwark Metal 21R81420 End Cap Model 21 R8 Insulation 14 Inches X 20 Inches","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe Southwark Metal 21R81420 is a Model 21 rectangular duct end cap designed for 14 inches x 20 inches duct openings with R8 insulation. End caps are essential components in HVAC duct systems. They seal off the open ends of rectangular ductwork, preventing air leakage and maintaining system efficiency. This model is built for professional HVAC installations where thermal performance and durability are required. The R8 insulation rating provides a higher level of thermal resistance compared to R4 or R6 options, making it a strong choice for conditioned spaces that demand tighter energy control. HVAC technicians and sheet metal contractors rely on end caps like this one to finish duct runs cleanly and securely. The 21R81420 is fabricated from hot dipped galvanized steel meeting ASTM A653 CS Type B standards. This galvanized coating protects the steel from corrosion and moisture, extending the service life of the duct system. The 26 gauge construction provides solid rigidity while remaining workable in the field. The S-Lock drive connection type allows for fast, reliable attachment to rectangular duct sections. An S-cleat option is also available for additional fastening flexibility. This end cap is manufactured in the USA and ships as a single unit. It fits into Southwark Metal Product Family 21, which covers a range of rectangular duct fittings for commercial and residential HVAC applications. Installers working on forced air systems, air handling units, or supply and return trunk lines will find this end cap a practical solution for terminating ductwork runs. Its rectangular shape and precise sizing ensure a consistent fit on standard 14 inches x 20 inches duct openings.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eHot dipped galvanized steel construction per ASTM A653 CS Type B for corrosion resistance and long service life\u003c\/li\u003e\n\u003cli\u003eR8 insulation rating for enhanced thermal performance in conditioned spaces\u003c\/li\u003e\n\u003cli\u003eS-Lock drive connection type with S-cleat availability for secure, fast field installation\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eProduct Highlights\u003c\/h4\u003e\u003cp\u003eThe Southwark Metal 21R81420 delivers a durable, insulated end cap solution for 14 inches x 20 inches rectangular ductwork. Its galvanized steel body and R8 insulation make it well suited for professional HVAC installations requiring reliable air sealing and thermal control.\u003c\/p\u003e\u003ch3\u003eProduct Information\u003c\/h3\u003e\u003ch4\u003eStandard Information\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: SOUTHWARK METAL\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 21R81420\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel\u003c\/strong\u003e: 21\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShape\u003c\/strong\u003e: Rectangle\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDuct Size\u003c\/strong\u003e: 14 inches x 20 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInsulation Rating\u003c\/strong\u003e: R8\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: Galvanized Steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGauge\u003c\/strong\u003e: 26 GA\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection Type\u003c\/strong\u003e: S-Lock Drive\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGalvanized Coating\u003c\/strong\u003e: Yes\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCountry of Origin\u003c\/strong\u003e: USA\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 3 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUnit of Measure\u003c\/strong\u003e: Each\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProp 65\u003c\/strong\u003e: Yes\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SOUTHWARK METAL","offers":[{"title":"Default Title","offer_id":51121078141234,"sku":"21R81420","price":26.9,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/304885251.webp?v=1777747771","url":"https:\/\/voomisupply.com\/products\/southwark-metal-21r81420-end-cap-model-21-r8-insulation-14-inches-x-20-inches","provider":"Voomi Supply","version":"1.0","type":"link"}