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 and 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. Additionally, the 81 and 81Z would see limited use in ground combat roles. The 81s in this lot share a mounting bracket attached to the heat shields that doubles as the mounting point for an included anti-aircraft sight, ribbed pistol grip with a single trigger, steel rod buttstock with canvas pad, and a swiveling ejector unit head. The receivers are configured with a mirrored feed and ejection system, each intaking the belt through a hinged chute and the ejected casings and belt going through the aforementioned ejection port, the casings dropping straight down and the belts passing through a channel which takes them through, over the top of the receiver, back down the opposite side and into the same port as the casings, all of which would be funneled into a catch tube. Each top cover bears the "byf" (Mauser) manufacturer code and "MG81" nomenclature, with the left and right components marked "L" and "R", respectively, sequential numbers on the covers and receivers, and a pull-cord charging handle mounted at the rear of each receiver.

Exceptionally fine, with 90% plus original combination blue/phosphate finish, showing a brown patina on the feeding/ejection hardware and some of the heat shield components, along with some mild edge wear and handling marks. Stock and grip are very fine and show minor wear. Mechanically untested. 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.

Exceptionally fine, with 90% plus combination blue/phosphate finish, showing a brown patina on the feed/ejection hardware, minor spotting and light handling marks. Stock and grip as described in A. Mechanically untested. 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.