It was designed by Christian Vanderpleyn and Michel Costa and entered into two races of the 1986 Formula One season, in Italy and Portugal, driven by Italian Ivan Capelli.
The single JH21C was built around a 1983 Renault RE40 monocoque[2] that had been acquired by team owner Henri Julien.
It was fitted with a Motori Moderni V6 turbocharged engine and Pirelli tyres, and painted in the white livery of the team's main sponsor El Charro, an Italian fashion company.
However, Pironi saw this test as a one-off and thus did not compete for the race seat with Capelli.
The car is now on display at the Manoir de l'Automobile in the commune of Lohéac, Brittany.