Absolutely wonderful lines and proportions! Derham built that design under license from Hibbard and Darrin who created it as their Torpedo Transformable four door convertible/phaeton with the top material flap between the side windows and second cowl windshield.
The convertible coupe version has the same low top, elegantly angled windshield and door frame with a low deck. In addition to Packard, they were mounted on Cadillac, Chrysler Imperial, Stutz, Hispano-Suiza and Rolls-Royce chassis, in either configuration.
There is a particularly gorgeous example extant on the '30 745 Deluxe Eight.....just stunning!