That's the Vauxhall-Villiers, based on an old TT Vauxhall from 1922. The brainchild of Raymond Mays (of ERA and BRM fame) and engineered by Amherst Villiers, sometimes raced under the title Villiers-Supercharge.
The tall figure to the right is Mays, and the shorter man must be Villiers, although it looks a lot like Humphrey Cook, who financed the ERA enterprise.
