1954 Jaguar launched its Malcom Sayer designed D-Type with incorporated aerodynamic headlamp covers. The D-Type's racing success made Jaguar renown worldwide..

1961 the same designer's E-Type became a bestseller, the most popular sports car at the time. This success was undoubted on the merits of its admirable design that yet again incorporated aerodynamic headlamp covers..

1967 US import regulations enforced production to be amended. Quote "but without transparent headlamp covers the front appeared entirely different, as if the Jaguar was suffering from a kind of eyeball prolapsus".
Source: Jaguar Geschichte-Technik-Sport, Motorbuch Verlag
 

Today an opportunity to correct this unfortunate deformity has come up. A retrofitting kit developed by the industrial designer Stefan Wahl allows to return to the genuine form, just the way Malcom Sayer would have wanted it.
Owners of E-type series 1 ½ through 3 can now enjoy the genuine shape.
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Future "Design quotes from Jaguar for Jaguar succeed in future, as Keith Helft adapts the E-Type to F-Type. No need to reinvent the most beautiful snout just as you would not reinvent the wheel". As a matter of course, the new F-Type features headlamp covers yet again.