Darth Vader's suit was a double-edged sword. While it was extremely durable and increased his physical strength, it was also bulky, painful to wear and inflexible. However, the Star Wars villain's chest plate buttons controlled many of the suit's life-support functions and were a means of control for Emperor Palpatine.

According to Star Wars: Darth Vader- A 3-D Reconstruction Log written by Dan Wallace, the top left corner of his chest plate holds three switches. The one at the top controls the neural system's data, the center controls the respiratory system's data and the bottom controls the circulatory system's data. To its right lies a blue and red button which control the suit's auto control functions and manual override, respectively. There are four more switches below those buttons; the grey ones are program switches meant for Darth Vader's convenience while the red switch to the right served as a system reset.

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Due to the chest plate's exposed external location, many of Darth Vader's life support functions were easily vulnerable to attack or sabotage, which happened twice in Star Wars Legends. In Sean Williams' novelization of The Force Unleashed II, these systems were severely damaged during Darth Vader's duel against Galen Marek, as he was caught in a field generator explosion. In the Evasive Action: Recruitment webstrip written by Paul Ens and illustrated by Tom Hodges, the cyborg Antinnis Tremayne easily deactivated the suit after pressing a single button. Despite its vulnerability, these appear to be the only times that Vader's systems were compromised before his final battle with Palpatine in Return of The Jedi.

In James Luceno's novel, Dark Lord: The Rise of Darth Vader, Palpatine reveals that he is extremely knowledgeable about the suit's delicate circuitry, including that its life-support functions are vulnerable to electrical discharges. This weakness would make Vader susceptible to Palpatine's favorite method of attack — Force Lightning. The chest plate's vulnerabilities were thus intentional, as Palpatine would use the threat of Force Lightning as a means of control against Darth Vader, who despised his Sith mentor. To his credit, he would later outfit his suit with electrical insulation, although it wasn't foolproof.

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Darth Vader's chest plate also went through some variations during the films. In Revenge of the Sith, the top blue button is green, while the switches at the bottom are reversed, with the red switch to the left of the grey ones. In A New Hope, this red switch is now white, while Empire Strikes Back and Return of The Jedi retain its best-known color-scheme.

Although it's not as iconic as his mask or cape, Darth Vader's chest plate was the most crucial component to his survival.

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