Bayonet M9 Low-poly 3D model

The M9 bayonet was designed and developed by Charles A. Mickey Finn at his R&D company, Qual-A-Tec. It is a refined copy of the Russian AKM 6H3 bayonet. He later produced it under the Phrobis III name, filling a military contract for 325,000 units. Buck Knives was contracted to make 300,000 units and sold a commercial version under their own name. Finn's designs proved extremely popular, and were widely counterfeited and sold illegally by other makers. In 1986, Finn received U.S. Patent 4,622,707, however, unlicensed copies continued to flow unchecked into the United States from Asia and Mexico, cutting into legitimate sales.

After the Phrobis III bayonet contract was completed, rights to the M9 reverted to the United States Army and there were many subsequent versions from other companies. It is issued by the armed forces of the U.S. and other countries, and has also been sold commercially in various versions.

Some production runs of the M9 have a fuller and some do not, depending upon which contractor manufactured that batch and what the military specs were at the time. The M9 Bayonet partially replaced the older M7 Bayonet, introduced in 1964. Although it has been claimed that the M9 may be more prone to breakage than the older M7, the M9 bayonet has a 20% thicker blade and tang (0.235vs. 0.195) and a 75% greater cross-sectional area of steel in the blade than the M7.