Metric Square Head Bolts

Metric Square Head Bolts are special threaded fasteners with a square head—shaped that way so you can use a wrench on them. Most follow ISO metric standards, like DIN 478 or DIN 479, and they make a strong connection.

Although metric square head bolts are not as popular as hex head bolts, they are still necessary components in some work scenarios where their unique shape is clearly required. You’ll often find them on older machines, in wood construction, or where you need a low-profile head that still transmits torque well. They’re a reliable, old-school way to fasten things.

Product Benefits

The main plus of Metric Square Head Bolts is that they don’t round off as easily when you tighten them a lot—even if your tools are a bit worn. The square head lets wrenches grip them well from different angles, and it makes them easier to install in tight spots where hex keys might not fit.

They also sit lower than regular hex bolts, and if you countersink them, they can sit flush with the surface. Their classic look is nice for restoration work too. These things have obvious characteristics and are particularly suitable for complex spaces that are difficult to maintain or particularly narrow places.

Material grade

Metric Square Head Bolts usually come in material grades like carbon steel 4.6, 8.8, and 10.9. If you need them for jobs with high stress, 10.9 grade (high tensile) ones are a good pick because they’re stronger. There are also stainless steel (A2/A4) and alloy steel options—these work better for resisting rust or when you need higher specs.

Product Parameters