Cyber-conversion unit
A Cyber-conversion unit was used in the process of "Cyber-conversion", as it was known by the Cybermen from the planet Mondas, and "upgrading" as it was known by the Cybermen of a parallel universe.
Cybus Industries cyber-conversion unit
A Cyber-conversion unit was created by John Lumic on a parallel Earth to "upgrade" humans into Cybermen. The main facility for conversions was Battersea Power Station in the London of the parallel universe. (TV: The Age of Steel)
Appearance
The Cyber-conversion unit took the form of a large device into which the subject was placed. It had four mechanical arms, mounted on a universal joint which was able to descend on the subject when a cyber-like head was lowered onto the subject. The arms consisted of two circular saws, several knife-like blades, a syringe filled with green liquid and a laser. (TV: The Age of Steel)
Earth built conversion unit
An Earth constructed conversion unit was constructed by the Cybermen upon arriving in the Doctor's universe. Unlike their standard conversion units, despite Yvonne Hartman's assumption, this unit was seemingly built to encase a human body into the suit of armour, rather than transplanting a human brain and torso into the suit and processing the part of flesh to fixed with the suit. This conversion unit was constructed from materials within Torchwood 1 and therefore not sucked into the void following the Cult of Skaro's arrival and defeat. (TV: Army of Ghosts)
These systems included a vaguely ovoid shaped gurney upon which the newly converted Cyberman stood or lay. One of these devices was taken by Ianto Jones and moved with his girlfriend Lisa Hallett attached and partially converted. Hallet was able to alter the system to transplant her brain into another person's body. (TV: Cyberwoman)
Primitive conversion
When they were stranded in the 19th century, the Cybermen transplanted the brains of cats and dogs into scrap metal bodies in order to create Cybershades. They also created a cyber headset that conditioned a victim's brain to make it the control unit for the CyberKing vessel. The CyberKing itself was also said to have a giant conversion factory concealed within its chest to convert whole populations but the ship was destroyed before the process could begin. (TV: The Next Doctor)
Mondasian Cybermen Cyber-conversion unit
The Cybermen from Mondas typically conditioned their subjects before Cyber-converting them. The unit used for this was frequently a wall mounted unit which conditioned and added various systems to the individual who was being converted. However even despite the conditioning it was possibile for individuals to fight the conditioning and escape the Cybermen's hold. (TV: Attack of the Cybermen, AUDIO: The Crystal of Cantus)
The Cybermen of the Cyber Legions also used conversion units; the entire body was placed into the suit. The first stage of conversion was purging of emotion, but this could be fought by individuals with strong emotions. (TV: Closing Time)