[4][5] The Type 90 designation is from the last two digits of its year of adoption, which was 2590 (or 1930 AD) on the Japanese Kōki calendar.

The Third Model (dating from late in World War 2) was simplified and manufactured with two barrels for ease of production.

The barrels were made from blued steel and the body of the weapon was painted with a black lacquer.

Third, US soldiers who found flare guns on the battlefield often threw them away, as they were not seen as collectable as pistols, rifles, or knives.

In Hollywood films like Demolition Man (1993) and Waterworld (1995), the Type 90 is used as a stand-in for a futuristic shotgun pistol.