. This is a sport-scale model of the S25-Berkut which was part of the first operational Surface-To-Air missile system. Developed in the USSR in the 1950's, it was intended to defend Moscow from aerial attacks. The large fins really make it stand out. The model rocket has an impressive 8.47" fin span and stands nearly 28" tall. The scale S25-Berkut missile flies D to F motors for a wide motor selection. As the tail-end is wider, the kit includes a plywood transition ring, and cardstock transition template. This is a Skill Level 4 kit.