Rust-eze is the sponsor printed on Lightning McQueen in Pixar's Cars.
Lightning begins the film as a talented but inexperienced rookie who is sponsored by the Rust-eze medicated bumper ointment brand. He dislikes the product's image and hopes to replace Rust-eze with the more prestigious Dinoco team after winning the Piston Cup.
The sponsor becomes an important part of Lightning's character arc. Rust-eze owners Rusty and Dusty help him after he reaches Radiator Springs, and their support contributes to his change from a self-centered racer into a more considerate teammate and friend.
Dinoco is the major sponsor Lightning wants, not the sponsor he starts with. The blue Dinoco racer Strip Weathers, known as The King, represents the brand during the first film's racing storyline.