This Relaxn 1/4" Npt x 1/2" Hose Tail Brass fitting links a 1/4 inch NPT fuel port to a 1/2 inch thirteen millimetre hose so you can keep fuel lines tidy on the boat. The NPT male thread suits filter heads and tanks with 1/4 inch ports so you can hook up standard marine fuel hose without odd adaptors or extra joints in the line. The body is solid brass with a machined 1/2 inch thirteen millimetre barbed tail so the hose bites down well under a clamp. The tapered 1/4 inch NPT thread pulls in tight on matching fittings which helps cut down on weeps around the tank or filter head. The hex section gives you a proper spanner grip which helps when you are leaning into a tight transom well to tweak the fuel setup.

• Relaxn brass hose tail fitting
• Part number 37288
• 1/4" NPT male tapered thread
• 1/2" (13mm) barbed hose tail
• Suits fuel filter heads and fuel tanks
• Intended for marine fuel hose applications
• Brass construction for general fuel resistance
• Hex section allows use of standard spanner
• Barbed tail helps secure hose under clamp
• Compact adaptor for joining hose to threaded ports

Q: Can this Relaxn brass hose tail be used with 1/2" fuel hose on a small outboard tank?

Yes, it suits 1/2" (13mm) hose and 1/4" NPT ports. The barbed tail is sized for 1/2" fuel hose, giving good grip under a clamp. The 1/4" NPT male thread matches many portable and fixed tanks. Always check your tank thread is 1/4" NPT before fitting.

Q: Is the 1/4" thread on this fitting NPT or BSP?

The thread on this fitting is 1/4" NPT. NPT uses a tapered thread profile, so it tightens progressively in a matching NPT female port. Using it in a BSP port can damage threads or leak, so confirm the port type on your fuel filter head or tank.

Q: What size spanner fits the hex section on this hose tail?

The exact spanner size is not specified. You can select a standard open-end or adjustable spanner that closely matches the hex flats. Always support the mating fitting when tightening. Avoid over-tightening into softer materials like aluminium heads.

Q: Is this hose tail suitable for diesel fuel as well as petrol?

Yes, brass fittings like this are commonly used with both petrol and diesel fuel. The smooth internal bore helps maintain flow for diesel return and supply lines. Always use approved fuel hose with a 1/2" (13mm) internal diameter. Inspect clamps and hose regularly in marine environments.

• Suits hose with internal diameter of 1/2" (13mm)
• Connects 1/2" fuel hose to 1/4" NPT threaded ports
• Intended for marine fuel filter heads and fuel tanks with 1/4" NPT female thread