Hi,
I hope this may assist you (this refers to WW1, but it will double up before hand):
3,7 cm AUTOMATIC MACHINE GUN (POM-POM)
German designation: 3,7 cm Maschinenkanone
Weight of projectile: 0,45 kg (1 lb)
Muzzle velocity: 550 m/sec (1 800 ft/sec)
Calibre: 3,7 cm (1,46 in)
Maximum range: 2 750 m approx (3 000 yds approx)
Weight in action: 757 kg approx (1 665 lbs approx)
Note: These details are approximate only and refer to pom-poms not of Krupp manufacture.
Hiram S. Maxim, an American, invented this quick-firing belt-fed gun. It achieved fame in the Boer War where it became known as the pom-pom. The British Army had earlier rejected it, but a number were ordered urgently when the Boer success with it was appreciated.
Later naval versions on deck mountings were produced. At the beginning of World War I modifications were made to allow these guns to be used against aircraft. The British Army also mounted pom-poms on high-angle carriages for the same reason. The Belgian and German armies did likewise.
The German pom-pom was made by Krupp and this is one of those guns. There were four in German West, the name by which South African troops came to know South West Africa. These guns were captured at Windhoek.
Pom-poms were not widely used in the war. As anti-aircraft guns they were soon replaced by guns specifically designed for that purpose.
Here are some photos from the Australian War Memorial Annex when I was there early this year:

