Rotax Throttle Return Spring. This spring is designed to ensure retraction of the throttle slide back to 'off throttle' position as the throttle pedal is released. Comically oversized for the application, this spring is fairly hard to lose, but also easy to warp or damage while working on the Dellorto VHSB Rotax carburetor.
Each spring is designed to fit into the carburetor above the throttle slide, and below the plastic carburetor cap.