A restraining bolt, also known as a restraining separator bolt, was a small device that could be attached to most droids used to ensure their obedience. More specifically, when fitted with a restraining bolt, droids could not leave the area designated by their owner, and were forced to obey commands given from a small remote device (such as "COME" and "STOP"). When activated, the restraining bolt turned off a droid's motor impulse without actually shutting down the droid. Restraining bolts had to be secured to specific locations on the droid.
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Sig by me
if you take it, the next morning ill be holding a knife to your throat and callin ya Charlie