The original model was the three-litre, but as customers put heavier bodies on the chassis, a larger 4½-litre model followed. Perhaps the most iconic model of the period is the 4½-litre "Blower Bentley", with its distinctive supercharger projecting forward from the bottom of the grille. Uncharacteristically fragile for a Bentley it was not the racing workhorse the 6½-litre was, though in 1930 Birkin remarkably finished second in the French Grand Prix at Pau in a stripped-down racing version of the Blower Bentley, behind Philippe Etancelin in a Bugatti Type 35.