Aluminum Flat Bar 3/8in x 3in x 12in (4pcs) - 6061 Solid Extruded

In this review the Therwen four-piece pack of aluminum flat bars is judged as a practical, no-nonsense option for DIYers and light fabricators who need consistent, corrosion-resistant mill stock. The review finds the set most useful because the bars are made from 6061 aluminum and come in a standardized 3/8in by 3in by 12in size, which makes them easy to handle, weld and finish for a variety of projects. The package precision and shiny finish are the single biggest reasons a hobbyist or tradesperson would buy these bars.

Key Features

• Pack Count: Four pieces included, which provides enough material for small multi-part projects or spares for future work.
• Material: Made from 6061 aluminum, offering reliable corrosion resistance and straightforward welding for repairs and fabrications.
• Size Precision: Each bar is 3/8in x 3in x 12in with metric manufacturing tolerances around 0.5mm, so dimensions are consistent for fitting and machining.
• Lightweight Design: The extruded flat bars are easy to lift and position, making them convenient for single-person installs and handheld work.
• Finish: A shiny silver surface that cleans up well and can serve as a visible decorative element in exposed applications.
• Versatility: Suited to home repair, construction trim, brackets, or creative DIY projects where a straight, flat aluminum element is needed.

Who It's For

This product suits DIY enthusiasts, hobby fabricators, and tradespeople who need short runs of flat mill stock with predictable dimensions and good corrosion resistance. Because the pack contains four identical bars, it is useful for creating matching brackets, trim pieces, or repeating elements where uniformity matters.

Those who need large structural members, custom alloys, or long continuous lengths should look elsewhere; this product is best for light to moderate loads and small assemblies rather than heavy structural applications.

Pros & Cons

Pros

• Made from 6061 aluminum, balancing strength and weldability for most workshop tasks.
• Four-piece pack gives extra material for multiple parts or backup pieces.
• Consistent 3/8in x 3in x 12in sizing with roughly 0.5mm tolerance helps with accurate fitting and repeatable results.
• Lightweight and shiny finish makes handling and cosmetic work easier.

Cons

• Not suitable for heavy structural loads or long-span applications where thicker or longer stock is required.
• Metric manufacturing tolerance of about 0.5mm means ultra-precision machine work may need additional finishing.

Specifications

Brand	Therwen
Material	6061 aluminum
Package Quantity	4 pieces
Cross Section	3/8in x 3in
Length	12in
Manufacturing Tolerance	approximately 0.5mm
Finish	shiny silver extruded surface

Our Verdict

The Therwen 4-piece 6061 aluminum flat bar pack is a sensible buy for hobbyists and light fabricators who need consistent, easy-to-use mill stock in short lengths. Its combination of weldable 6061 alloy, tidy finish, and four-piece count offers good value for repair, trim, and small fabrication work, though it is not intended for heavy structural use.

Frequently Asked Questions

Are these bars weldable?
Yes, the 6061 alloy is commonly welded and the bars are described as easy to weld for typical workshop techniques.

What is the length and cross section?
Each bar measures 12in long with a cross section of 3/8in x 3in.

How precise are the dimensions?
The product is made to metric standards with a margin of error of about 0.5mm, so minor finishing may be needed for precision fits.