Weight Gain 4000 is a fictional brand of protein shakes that appeared in the Season One episode, "Weight Gain 4000".
Background
Eric Cartman begs his mother for Weight Gain 4000 after seeing the commercial on TV. Thinking it will enhance his personal appearance for the Kathie Lee Gifford award show, without physical exercise, but instead he ends up looking like an overweight blob.
Cartman shouts the catchphrase "Beefcake!" mimicking the commercial whenever referring to the product. During "City on the Edge of Forever (Flashbacks)", Cartman remembers he looked more in shape and muscular during the Kathie Lee Gifford award show.
Appearance
The product is a green can with a black lid. On the face of the can, there is an image of a muscular man and "WEIGHT GAIN 4000" printed in yellow text.