Measuring 4" high, we have the Optimus Prime Figural Keychain taken straight out of the second Transformers live action movie, Transformers: Revenge of the Fallen!  This Optimus Prime Figural Keychain features moving arms and legs as well as moving casings on his thruster packs...or whatever the technical jargon may be for those.  Hopefully, this Optimus Prime Figural Keychain won't be such a wuss when facing the Megatron Figural Keychain. WUSS!