This is a specific hardware piece for custom fabrication, plumbing, or automotive work.

It's a straight 'weld-on bung' with a 3/8-inch barb on one end.

In simpler terms, it's a small aluminum fitting.

One end is a barbed nipple (the 'barb') designed to grip a piece of 3/8-inch inner diameter hose or tubing – you slide the hose over it and clamp it down for a secure connection.

The other end is a plain cylinder meant to be welded onto a tank, pipe, or other metal surface, creating a permanent port.

It's made from precision-machined aluminum alloy, which is strong, lightweight, and corrosion-resistant, making it good for things like intercooler piping, coolant overflow tanks, air intake systems, or custom fluid reservoirs.

The finish is a natural silver aluminum color.

This isn't a plug-and-play consumer item; you need welding equipment and knowledge to install it properly.

But if you're building or modifying something and need a reliable, clean way to attach a hose line, this is a fundamental and useful fitting to have on hand.