 
 <prompt> Wetin be di unit of measurement wey dem dey use for di guns? Based on di question wey dey above, write one context wey go contain di answer. E fit be 1 - 20 sentences. Context: <response>: The US finish World War I with two 3-inch AA guns and dem make improvements throughout the inter-war period. But for 1924 dem start work on top new 105 mm static mounting AA gun, but na only few dem produce by mid-1930s because by that time dem don start work on top 90 mm AA gun, wey get mobile carriages and static mountings wey fit engage air, sea and ground targets. The M1 version na im dem approve for 1940. During the 1920s dem do small work on top 4.7-inch wey dem abandon, but dem come back to am for 1937, wey lead to new gun for 1944. 