Think hen's teeth! Should be really early Renault 4 looking but with the rear windows in metal, deck chair seats, grille pressed into the bonnet, and no door trims, hubcaps (or anything else they felt they could leave out without stopping the car from running). 3 speed gearbox too, but the R4 had 3 speeds until 1968(ish) as well so that's not the reason for the name. Name was based on the engine which was even smaller that the early R4 unit (600cc ish).
Renault didn't sell many (because it was rubbish and not so much cheaper than the 4) so stopped production in about 1962. Go for it. I'll have it if you don't want it.