SKU: CW74232
UPC: 742985143968
MPN: IBVF-1250
The GROCO 1-1/4" Bronze NPS to NPT Flange Adapter (model IBVF-1250) solves a critical compatibility problem in marine plumbing systems. This bronze flanged adapter bridges the gap between National Pipe Straight (NPS) thru-hull fittings and National Pipe Tapered (NPT) threaded in-line valves, eliminating dangerous thread mismatches that can compromise hull integrity and create dangerous leaks on boats operating in saltwater or freshwater environments.
Cast from marine-grade bronze, this adapter accepts standard thru-hulls into its base flange and accommodates standard in-line valves on top, creating a safe and structurally sound assembly. The 1-1/4" diameter specification matches common marine through-hull sizes found on mid-sized fishing vessels, cruising boats, and commercial marine applications. The flanged design distributes pressure loads evenly across the hull fitting, preventing stress concentration that can lead to cracking or seal failure over time. When used as a seacock adapter, the GROCO IBVF-1250 provides the mechanical stability required for reliable emergency shut-off valve installation.
This adapter is essential for boat owners retrofitting seacock systems, original equipment manufacturers standardizing thru-hull configurations, and marine technicians who need to install modern valves on vessels with legacy fittings. The bronze construction resists corrosion in saltwater environments where standard steel fittings would deteriorate rapidly. Whether installing a new through-hull assembly or upgrading an existing seacock system, the GROCO NPS-to-NPT flange adapter ensures thread compatibility without modification to hull or valve components.
GROCO marine fittings are designed to meet the demands of saltwater environments and are widely specified in marine construction. The 1-1/4" size represents a popular mid-range diameter for sea-cocks on boats ranging from 25 to 50 feet, making this adapter a standard choice in marine service shops and boatyards across North America.
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