Robobros were a race of robots who acted like the stereotypical "bro-culture" found on Earth. They were killed when Rick Sanchez (C-132) managed to set off their self-destruct sequence on Flarbellon-7.
All Robobros wear some form of hat, most commonly a cap, almost exclusively backwards. A fair amount of them also either wear sunglasses, or were built to look like they wear sunglasses. The mouth-section of their face flashes green if they smile and red if they frown.
Robobros behave in a stereotypical macho manner, using the terms "bro" or "dude" whenever they speak. They also have a clear fixation with working out, partying and drinking. They are also very violent, shooting lasershots out of their hands. Rick said that the only way to defeat Robobros is to "wait twenty years when they put on weight and realize they wasted their lives".
When Rick, Morty and Summer of Dimension C-132 ventured to Flarbellon-7 to acquire Penp Juice, they met Peacock Jones and his companion Barbarica, for whom he has staged a fight at the deserted planet with the Robobros. He did not anticipate Rick and Morty being there and certainly not Morty clubbing a Penp out of the sky to fall on Barbarica and crush her to death. Following this, Rick managed to initiate the robots self-destruct function, killing all the Robobros.