Brass Pipe Bushing 1″ x 3/4″ NPT Marine Plumbing Reducer Fitting

A compact, reliable brass reducer bushing for marine plumbing systems. This 1″ male NPT x 3/4″ female NPT bushing steps down a 1″ threaded port to accept a 3/4″ fitting, hose barb, or valve one of the most common size transitions in marine raw water, bilge, and freshwater plumbing runs.

Machined from solid brass, it resists corrosion in both freshwater and saltwater environments and forms a pressure-tight seal when used with marine-grade thread sealant. The NPT taper thread engages progressively as the fitting is tightened, eliminating the need for a separate gasket.

Key Features

Size: 1″ male NPT x 3/4″ female NPT (reducer bushing)
Material: Solid brass corrosion-resistant in freshwater and saltwater
NPT taper thread pressure-tight seal without a separate gasket
Suitable for bilge, raw water, freshwater, and general marine plumbing
Use with marine-grade PTFE tape or pipe thread sealant for a leak-free connection

Best Use Case

Best suited for stepping down a 1″ threaded port or fitting to a 3/4″ connection in marine plumbing systems common in raw water intake lines, bilge pump discharge plumbing, freshwater system connections, and engine cooling circuits. Always apply marine-grade PTFE tape or pipe thread sealant to NPT threads before assembly. Do not overtighten NPT threads seal through taper engagement and excessive torque can crack brass fittings.

Parts Desk Insights

The 1″ x 3/4″ size is one of the most frequently requested brass bushing sizes it covers a wide range of common plumbing transitions on production boats. When a customer needs this fitting, confirm whether they need a bushing (male-to-female, which this is) or a coupling (female-to-female) before ordering. Cross-sell with other sizes in the brass bushing range as needed: 1-1/4″ x 3/4″ Brass Bushing, 1-1/2″ x 1-1/4″ Brass Bushing, 2-1/2″ x 2″ Brass Bushing, and 3″ x 2-1/2″ Brass Bushing. For elbow fittings in the same plumbing run, see the Brass 90 Elbow 1″ NPT.