Groco HTH-S Series Stainless Steel Thru-Hull Fittings - 316 Stainless, Available in 1.25" to 1-1/2" Hose Barb

The Groco HTH-S Series thru-hull fittings are precision-machined from 316 stainless steel, the corrosion-resistant alloy of choice for below-waterline hardware exposed to constant saltwater immersion. Each fitting installs through the hull to provide a secure, UL-listed connection point for engine cooling intakes, washdown pumps, livewell systems, and other onboard plumbing that draws water from outside the hull. A straight hose barb outlet paired with NPT threading makes for a reliable, leak-resistant hose connection, and each unit ships complete with its mounting nut for a proper through-hull seal.

Specifications

• Brand: Groco
• Material: 316 Stainless Steel
• Connector Type: Hose Barb
• Thread Type: NPT
• Certification: UL Listed 647B
• Quantity: 1 piece (includes mounting nut)

Sizes & Options

The HTH-S Series is available in two hose barb sizes: 1.25" (HTH-1250-S) and 1-1/2" (HTH-1500-S). Match the fitting to the inside diameter of the hose already installed on your intake or discharge line - undersized fittings restrict flow, while oversized fittings will not seat properly on the hose. Confirm your existing hose ID before ordering, and inspect the hull thickness at the install location to ensure the barb length and mounting nut provide adequate clamping engagement.