The Parabellum MG14 was a 7.92×57mm caliber machine gun built by Deutsche Waffen und Munitionsfabriken. Around three versions survive till today, a water cooled, an air-cooled, and a 14/17 version with a 3x telescopic sight.
The Parabellum MG14 is a redesign of the MG 08 intended for aircraft use. The main visible difference is that the MG14 doesn't need water cooling, and primarily uses an air cooling jacket.
The MG14/17 is a revised version of the MG14 that reduces the size of the voluminous running casing. It also has a mounting rail for scopes.