By 2005, the Autobots had appropriated the Spy Cassette technology from the Decepticons, and constructed a cassette force for Blaster to rival Soundwave and his Spy Cassettes.The Autobot Cassettes first appeared during the Autobot City Massacre, when Soundwave deployed his own cassettes to demolish Blaster's communications tower, and stop his SOS message from reaching Optimus Prime on Moonbase One. Perceptor struggled with the cassettes, until Blaster came to the rescue, ejecting his four cassettes - Steeljaw, Ramhorn, Eject, and Rewind - who quickly saw off the miniature Decepticons. Shortly thereafter, Prime arrived from Cybertron with reinforcements. Blaster and his cassettes had turned the tide of the battle.
There is little specific information available on each individual cassette. Ramhorn resembles a full-sized rhinocerous in robot mode, while Steeljaw resembles a full-sized lion. Eject and Rewind are twins, with matching robot modes, the only difference being in colour scheme - Eject is blue, while Rewind is black. Eject is the only cassette to achieve anything of note, as he was among the small group of Autobots who travelled back in time and actually helped begin the rebellion against the Quintessons that resulted in history as we know it.
The fates of the various Autobot Cassettes following the restoration of Cybertron's Golden Age are unknown.