Colonel T.R. Edwards was able to covertly install a synchro cannon on the Shimakaze-class battle cruiser, Icarus. He revealed this weapon over Optera when it was used to critically damage the Tokugawa, which had been dispatched to hunt him down. (Comic: "Robotech: Prelude to the Shadow Chronicles 2: Retribution") Other REF ship classes were retrofitted with synchro cannons, including the Garfish-class and the SDF-4. A smaller version was also developed and equipped on some Shadow Beta fighter. (Robotech: The Shadow Chronicles)