S1

In 2020 SCX launched four different versions of the Audi S1 WRX (FIA World RallyCross). This model with reference U10320S300 was sold in a classic single-box version and in a circuit version with tinted windows that conceal the interior. In this case the circuit version comes with rear-wheel drive and has no lights or driver figure. In red and white, #40 with "SONAX" livery, it carries Ekström's name on the rear windows. The model is a replica of the car that competed in the 2019 World RallyCross Benelux round at the Spa-Francorchamps circuit in Belgium.

The Audi S1 WRX was a rallycross car developed by Audi Sport for the FIA World Rallycross Championship between 2014 and 2019. It featured a turbocharged engine producing around 600 bhp, quattro four-wheel drive and acceleration from 0 to 100 km/h in under two seconds. In 2019 Mattias Ekström drove an Audi S1 in the RallyCross Benelux round at the Spa-Francorchamps circuit in Belgium, although he did not manage to qualify for the final knockout stages. The car in which he contested that round was used by SCX as the model for this exclusive circuit car.