The Japanese Navy used several different types of flare pistols during World War Two (and in the decades before), but the most impressive looking of the bunch was the three-barreled Type 90 (not to be confused with the two-barreled model also designated Type 90). The three barrels were not simply there to look intimidating, of course, but rather so that a flare of each of the three different colors in use could be kept ready at all times. The barrels were marked with colored decals to note the flare colors - one green, one white, and one red and yellow. In another unusual design decision, the entire upper assembly of the Type 90 is on a sliding spring-loaded track to absorb recoil.
For more information on Japanese flare pistols, see Teri's page at Nambu World: http://www.nambuworld.com/fgflareguns.htm
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