They dress and act in the manner of a modern hillbilly.
Fletcher McGee is dark green and shaped like a circle and has two black sideburns.
Clem looks identical to Plankton except with a bottle he often carries and a brown hat.
Unlike Plankton, they are not evil. However, they are perfectly fine with doing Plankton's evil bidding as long as he provides them with various rewards, such as memory for their laptops, an extra string for a banjo, matching boots, and most importantly root beer, which seems to be their favorite beverage.
One of Plankton's many cousins is mentioned in the episode "The Algae's Always Greener" when Plankton says he has not reviewed anything except for foreign exercise videos that one of his cousins sent him.
All except for Clem can read.
At most parts, they are repeated.
At first, when they are shown standing around the Krusty Krab, there would be trillions of them, but later when they start storming in there is a lot less of them.