High Quality Content by WIKIPEDIA articles! The Flexon was a downhill ski boot introduced by Raichle in the winter of 1980/81. Based on designs by Sven Coomer, Al Gross and Erik Giese, the Flexon used a unique system to control forward flex in a predictable way, as well as making the boot more comfortable and easier to put on and remove. The basic layout was, and is, generally referred to as a "three-piece" design -- three-piece boots preceding the Flexon included the Henke Strato, Nordica Comp 3 and a dozen other designs from Italian bootmakers.