The Champion was the “Chevrolet” of Vibroplex bugs. It used the assembled frame and flat pendulum of the Lightning Bug, but had a simplified damper assembly and lacked a circuit closer (shorting switch). It was the lowest-priced Vibroplex, handled well, and could send good code a bit slower than the round-pendulum models. Consequently, Champions are probably the second most common Vibroplex.
When the Champion was introduced in 1940, it came in only one base finish, black crackle. In the mid-Fifties the standard Vibroplex base color was changed to gray, and the Champion came only in gray. Like the Lightning Bug and Original, some Champions were made with Sienna brown and beige bases around 1980. Vibroplex quit making the Champion about that time, but you could buy a gray-base Champion from Vibroplex for more than ten years after that. The simple damper assembly on the Champion is called an “I” damper.