{"product_id":"bk-521-802bg-malleable-black-iron-pipe-plug-3-8-in","title":"Bk 521-802BG Malleable Black Iron Pipe Plug 3\/8 in","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe BK 521-802BG is a 3\/8-inch malleable black iron pipe plug designed to seal threaded pipe openings in gas, water, and general plumbing systems. Manufactured from black malleable iron meeting ANSI\/ASTM A-197 material standards, this plug provides a durable, pressure-rated closure for pipe ends and unused outlet ports. Threads conform to ANSI B1.20.1 for reliable engagement with standard NPT fittings. Dimensions meet ANSI\/ASME B16.14 and B16.39 specifications. Each fitting is 100 percent inspected and quality tested before shipment. Plumbers, pipefitters, and HVAC technicians reach for this plug when capping low-pressure gas lines, water distribution branches, or hydronic heating circuits.\u003c\/p\u003e\u003cp\u003eThis plug is suited for residential and light commercial plumbing and HVAC piping applications where a threaded pipe end must be sealed. Common install scenarios include capping unused tee or cross outlets, plugging test ports after pressure checks, and sealing branch lines during system modifications. The 3\/8-inch size covers one of the most frequent small-diameter fitting needs in both new construction and service work. Each fitting is individually flag tagged for identification, and the Mueller logo is cast into the body.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003eBlack malleable iron construction meets ANSI\/ASTM A-197 material specification\u003c\/li\u003e\n\u003cli\u003eThreads conform to ANSI B1.20.1 for standard NPT compatibility\u003c\/li\u003e\n\u003cli\u003eDimensions meet ANSI\/ASME B16.14 and B16.39 standards\u003c\/li\u003e\n\u003cli\u003e100 percent inspected and quality tested\u003c\/li\u003e\n\u003cli\u003eIndividually flag tagged for easy identification on the job\u003c\/li\u003e\n\u003cli\u003eMueller logo cast into fitting body for brand verification\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned as an OEM-style replacement or new-installation fitting for standard 3\/8-inch NPT threaded pipe systems in plumbing, HVAC, and general piping applications.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eInstallation is performed by licensed plumbers or pipefitters following applicable local codes and IFGC or IPC requirements depending on the service. Depressurize and isolate the line before threading the plug into the fitting to avoid injury. Use appropriate pipe thread sealant or PTFE tape on the threads as required by the system fluid and code. Do not overtighten malleable iron fittings, as excessive force can crack the casting.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: Malleable Black Iron\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial Standard\u003c\/strong\u003e: ANSI\/ASTM A-197\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDimension Standards\u003c\/strong\u003e: ANSI\/ASME B16.14, B16.39\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Standard\u003c\/strong\u003e: ANSI B1.20.1\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Size\u003c\/strong\u003e: 3\/8 inch NPT\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 0.022 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSold As\u003c\/strong\u003e: Each\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eStandard Information\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: BK\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 521-802BG\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"B\u0026K","offers":[{"title":"Default Title","offer_id":51345280467250,"sku":"521-802BG","price":19.5,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/310549880.jpg?v=1782053852","url":"https:\/\/voomisupply.com\/products\/bk-521-802bg-malleable-black-iron-pipe-plug-3-8-in","provider":"Voomi Supply","version":"1.0","type":"link"}