Brass Hose Barb reducer 3/8" to 5/16" ID hose Barb Fitting Hex Splicer Mender Union Air Water Fuel with hose clamps Tubing Adapter (Pack of 3)

Two hoses, two diameters, and nothing in the drawer to join them. It is a common way for a straightforward job to stop halfway. This is the straight-through answer: a 3/8" barb at one end, 5/16" at the other, with a hex band across the middle for a spanner. Three in the pack.

Why brass keeps turning up in fluid work

The supplier lists three properties, and each earns its place. Corrosion resistance is the obvious one on a fitting that will sit in a damp engine bay for years. Ductility at high temperature is the reason a brass barb tolerates being clamped hard without cracking the way a cast alloy can. Low magnetic permeability matters far less on a car than it does in instrumentation, but it is what the supplier states, and it is published here as printed rather than dressed up as something else.

The barb length does the holding

The supplier makes a point of the stems being long, describing them as long enough that a hose can be pushed well on and is not easily pulled off again. That is the sensible way to read a barbed union: the clamp squeezes, but the ribbed length is what resists the hose walking off under vibration. The hex in the centre gives you something to hold while a clamp is tightened, rather than twisting the hose that is already on.

Key features

• Three per pack: a spare and a second job covered.
• 3/8" to 5/16" step: joins two hose sizes in a straight run.
• Hex centre band: hold it with a spanner while a clamp goes on.
• Brass throughout: the material the supplier states for the union.

Specifications

• Quantity: pack of 3
• Hose sizes: 3/8" ID one end, 5/16" ID the other
• Type: straight reducing barbed union, hex centre
• Material: brass
• Pressure rating: not published — no working figure and no burst figure
• Temperature rating: not published
• Overall length and barb length: not published
• Stated applications: patio and lawn/garden hose connection, irrigation, temperature control circuits, pneumatic circuits, vacuum and fluid system test apparatus, lubricant and coolant lines (air, water, fuel, boat, gas)

Pressure, clamps and what is actually in the pack

• The product title says "with hose clamps". The supplier's own description never lists clamps among the contents and gives no clamp size or type. Treat the fittings as supplied on their own and confirm before ordering if clamps matter.
• No pressure rating and no temperature rating are published for these unions. Never assume a fitting is rated to the hose it joins, or a hose to the fitting.
• Fuel and coolant lines are pressurised and hot. Choosing hose and clamps suited to the fluid, the pressure and the temperature of your own system is the installer's responsibility.
• The application list above is the supplier's. It names fuel, water, air, gas, lubricant and coolant. It does not name brake fluid, ethanol blends or fuel injection systems, and no suitability for those is stated or implied here.
• A fuel leak is a fire risk. Have any fuel line work done by someone competent and check the join under pressure before driving.

Three unions in a drawer is the difference between finishing tonight and finishing on Saturday.

Returns, Refunds, and Replacements

Products that are received faulty, damaged, or not as described are eligible for a return, refund, or replacement in accordance with the Australian Consumer Law (ACL). We are committed to ensuring all products meet the standards of quality and reliability expected by our customers. However, please note that we do not accept returns or provide refunds for change of mind. We encourage you to carefully consider your purchase to ensure it meets your needs and expectations.

Delivery Timeframe

Please note that we cannot guarantee the exact date of arrival, and the delivery timeframes (excluding weekends and public holidays) are as follows:

For customers in Victoria, approximately 7-10 working days;
For customers in NSW, SA, ACT, and QLD, approximately 9-12 working days;
For customers in WA, NT, and TAS, approximately 9-12 working days.