The Type 91, 105 cm howitzer was a 105 mm (4.13 in) howitzer used by the Imperial Japanese Army during the Second Sino-Japanese War and World War II. As the standard Japanese light howitzer of the period, it was influenced by Schneider designs and was considered to be light, robust and reliable. Type 91 howitzers were issued to artillery regiments where they would supplement 75mm field guns. The Type 91 number was designated for the year the gun was accepted, 2591 in the Japanese imperial year calendar, or 1931 in the Gregorian calendar.
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