Brett Boag holds a small square of what appears to be ordinary wooden, 20-millimetre-thick chipboard.

Only this material is heavier and startlingly stronger.

Bulletproof in fact.

During a recent test in the United States, it withstood even a burst from a high-powered AK-47.

“It’s phenomenally tough. We’re making products that are even way in excess of the hardest hardwoods, very high impact resistance as well,” said Mr Boag, who manufactures construction materials at a factory east of Melbourne.

The products are made from hemp — one of the toughest plants on the planet. …