Developed as a replacement for the MG15 machine gun, the MG81 was intended for use as aircraft armament in flexible mounts, both as individual weapons an in the "MG81Z" twin mount configuration. The MG81Z was installed in many German aircraft in the intended flex mount role, along with being used in fixed rear-firing defensive mounts on the Do217 bomber and used in the ground attack role by putting three MG81Zs in a gun pod (six total machine guns per pod) for strafing attacks. The 81s in this lot share a swiveling mounting bracket attached to the heat shields and a spade grip unit with extended trigger levers mounted at the rear (the aforementioned apparatus is all professionally modern made). Unlike the more common MG34 and MG42 machine guns, the recoil springs are set inside the main body of the receiver, and the feed mechanisms are mirrored, with a swiveling feed chute on each side and a belt link chute running from the interior back out to the sides. Each has a top cover bearing the "MG81" nomenclature, "byf" (Mauser) manufacturer code, Krieghoff proofs and numbers "32175a" and "32176a" respectively. The Krieghoff proofed receivers are also sequentially numbered "11231a" and "11232a", with steel cable pull-cord charging handles and unified trigger housing with push-through safety.

Very fine, with 80% of the black finish on the barrel and barrel shroud and 95% of the phosphate finish on the receiver and dust cover, with mild wear and spotting overall. The grips show light scuffing. Mechanically fine. NOTE: This weapon is a National Firearms Act (NFA), fully transferable Class 3, which is registered with the Bureau of Alcohol, Tobacco, Firearms and Explosives, (BATFE) that is classified as a "Curios or Relic" as defined in 27 CFR, 478.11. These weapons are still subject to the provisions of 18 U.S.C. Chapter 44 and 27 CFR part 479.

As described in A.

Very fine, with 80% of the black finish on the barrel and barrel shroud and 95% of the phosphate finish on the receiver and dust cover, with mild wear and spotting overall. Mechanically fine. NOTE: This weapon is a National Firearms Act (NFA), fully transferable Class 3, which is registered with the Bureau of Alcohol, Tobacco, Firearms and Explosives, (BATFE) that is classified as a "Curios or Relic" as defined in 27 CFR, 478.11. These weapons are still subject to the provisions of 18 U.S.C. Chapter 44 and 27 CFR part 479.