Robot Krabs has the same coloration of Mr. Krabs, but can clearly be seen as different from each other. The mouth of the robot acts as a speaker for Plankton to talk through. Inside the robot are the controls for Plankton to operate it, there is also a self destruct slot for a penny to be inserted where the belt for the "pants" are. The robot also tends to make robotic noises and also has an exhaust pipe coming out of the back.
The robot first appears in "Imitation Krabs" when Plankton uses the robot to try and trick SpongeBob. The robot also has cameos in the episodes "New Leaf" and "Spy Buddies."