Unite your favorite characters from across the Transformers universe with the Transformers Power of the Primes Evolution Optimus Prime figure. Convert the 5.5-inch (14 cm) Orion Pax robot action figure into a 9-inch (22.5 cm) Optimus Prime robot figure using the included Evolution Armor piece. Orion Pax figure changes from robot toy to truck toy in 15 steps; Optimus Prime figure changes from robot toy to tractor-trailer toy in 33 steps. Set includes a Matrix of Leadership accessory that can fit inside Optimus Prime figure's chest. A great gift for collectors of Transformers action figures ages 8 and up.