This is an injection-plastic detail parts set for use with aircraft kits.
From the Revell website:
At the height of the Cold War, both the United States and the USSR possessed over 30,000 nuclear weapons. Among these weapons were thousands of missiles capable of being fired to targets half way around the globe. No matter whether they are launched from silos, submarines or strategic bombers, the sum effect of these nuclear stockpiles is the total annihilation of all life in both countries. This kit features nine U.S. missiles and eleven Soviet missiles with a display base and accurate decals.