The British Mark I Sprite was known as the Frogeye in the U.K. and the Bugeye in the U.S. because of its distinctive headlights mounted on top of the centre bonnet (hood). The mounted headlights were not actually part of the original car design; they were originally going to be mounted into the front of the car so they could "flip up" when they were in use, with the lenses facing skyward when not in use. However, mounting production costs lead to the flip-up headlight idea to be abandoned and so the headlights were simply mounted in a permanent upright position leading to the car's most unique feature.
The front sheet-metal assembly – bonnet and wings – was a one piece unit, hinged from the back, that swung up to allow access to the engine compartment. Both the engine and suspension were derived from the Austin A35 & Morris Minor models, also products of BMC. It used the 948cc engine fitted to these models upgraded with twin 1 1/8" inch SU carburettors. The front suspension was a coil spring and wishbone arrangement, with the arm of the Armstrong lever shock absorber serving as the top suspension link. The rear axle was both located and sprung by quarter-elliptical leaf springs, again with lever arm shock absorbers. There were no exterior door handles; one reached inside to open the door. There was also no boot (trunk) lid, and access to the spare wheel and rear storage was gained by tilting the seat backs forward and reaching under the rear deck.
