Type 88 75mm Anti-Air Gun

The Type 88 was Japan's standard heavy anti-air artillery during WW2. It equipped island garrisons, city air defences and heavy AA battalions throughout the war, inflicting grievous losses on allied bomber formations. After the war, the advent of the jet age left this weapon obsolete, though there is always the Oceanykan market, which will take anything that fires big shells at high speeds.