{"product_id":"brass-adapter-1-g-female-1-1-2-npt-male","title":"1\" G Thread (BSPP) Female to 1 1\/2\" NPT Male Adapter - Lead Free","description":"\u003cp\u003eIf your fixture ends in a \u003cstrong\u003e1\" G (BSPP) female\u003c\/strong\u003e thread and the pipe you're connecting it to runs \u003cstrong\u003e1 1\/2\" NPT male\u003c\/strong\u003e, this is the piece that bridges the two without cutting into your existing plumbing. It's cast from lead-free brass and comes with a washer already sized for the G thread side.\u003c\/p\u003e\n\u003ch3\u003eThread Types\u003c\/h3\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eFemale end\u003c\/td\u003e\n\u003ctd\u003e1\" G (BSPP), parallel thread\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMale end\u003c\/td\u003e\n\u003ctd\u003e1 1\/2\" NPT, tapered thread\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eWhy This Combination\u003c\/h3\u003e\n\u003cp\u003eA 1 1\/2\" NPT male end is larger than the standard 3\/4\" or 1 1\/4\" sizes in this range, so it's typically used where higher flow matters — main supply runs, larger shower valve bodies, or commercial-grade fixtures feeding into a G-threaded component.\u003c\/p\u003e\n\u003ch3\u003eWhat's In The Box\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e1 adapter (1\" G female × 1 1\/2\" NPT male)\u003c\/li\u003e\n\u003cli\u003e1 sealing washer\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eBuild Details\u003c\/h3\u003e\n\u003ctable style=\"width: 99.9589%; height: 117.5px;\"\u003e\n\u003ctbody\u003e\n\u003ctr style=\"height: 19.5833px;\"\u003e\n\u003ctd style=\"width: 46.9901%; height: 19.5833px;\"\u003eSKU\u003c\/td\u003e\n\u003ctd style=\"width: 50.5495%; height: 19.5833px;\"\u003eCSSL56160970\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 19.5833px;\"\u003e\n\u003ctd style=\"width: 46.9901%; height: 19.5833px;\"\u003eMaterial\u003c\/td\u003e\n\u003ctd style=\"width: 50.5495%; height: 19.5833px;\"\u003eLead-Free Brass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 19.5833px;\"\u003e\n\u003ctd style=\"width: 46.9901%; height: 19.5833px;\"\u003eFinish\u003c\/td\u003e\n\u003ctd style=\"width: 50.5495%; height: 19.5833px;\"\u003eBrass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 19.5833px;\"\u003e\n\u003ctd style=\"width: 46.9901%; height: 19.5833px;\"\u003eInstallation\u003c\/td\u003e\n\u003ctd style=\"width: 50.5495%; height: 19.5833px;\"\u003eScrew-In\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 19.5833px;\"\u003e\n\u003ctd style=\"width: 46.9901%; height: 19.5833px;\"\u003eOverall Length\u003c\/td\u003e\n\u003ctd style=\"width: 50.5495%; height: 19.5833px;\"\u003eNot Provided\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 19.5833px;\"\u003e\n\u003ctd style=\"width: 46.9901%; height: 19.5833px;\"\u003eHex Size\u003c\/td\u003e\n\u003ctd style=\"width: 50.5495%; height: 19.5833px;\"\u003eNot Provided\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eFitting It Together\u003c\/h3\u003e\n\u003col\u003e\n\u003cli\u003eCheck both ends against your existing pipework before threading anything in — 1\" G female on one side, 1 1\/2\" NPT male on the other.\u003c\/li\u003e\n\u003cli\u003eSet the washer into the G thread side first. That's where the seal actually happens, not on the NPT side.\u003c\/li\u003e\n\u003cli\u003eThread by hand, then bring it up snug with a wrench sized to the hex.\u003c\/li\u003e\n\u003cli\u003eTape or sealant on the NPT threads is optional, not required for the seal.\u003c\/li\u003e\n\u003cli\u003eTurn the water on and check the joint before you call it done.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003ch3\u003eCommon Questions\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eWhy does the G side need a washer but the NPT side doesn't?\u003c\/strong\u003e\u003cbr\u003eG (BSPP) threads run parallel and can't seal on their own, so they rely on a washer. NPT threads taper and bite down as they're tightened, which creates the seal on that end.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs 1 1\/2\" NPT bigger than the 1 1\/4\" version you sell?\u003c\/strong\u003e\u003cbr\u003eYes — this is the larger of the two. Double-check the size stamped or labeled on your existing fitting before ordering, since they're not interchangeable.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I use this on a main water line, not just a fixture?\u003c\/strong\u003e\u003cbr\u003eIt's suited to that — the larger NPT end is generally chosen for higher-flow or supply-line applications rather than a single small fixture.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes the brass contain lead?\u003c\/strong\u003e\u003cbr\u003eNo, it's lead-free brass, suitable for potable water.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat if my thread is G 1\" but slightly different from BSPP?\u003c\/strong\u003e\u003cbr\u003eG thread and BSPP refer to the same British Standard Pipe Parallel standard, so if your fitting is marked G1\" or 1\" BSPP, it should match.\u003c\/p\u003e","brand":"Cascada Showers","offers":[{"title":"Default Title","offer_id":47531800002731,"sku":"CSSL56160970","price":36.95,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0249\/1813\/0722\/files\/CSSL56160970_1.jpg?v=1786440400","url":"https:\/\/cascadashowers.com\/products\/brass-adapter-1-g-female-1-1-2-npt-male","provider":"Cascada Showers","version":"1.0","type":"link"}