The mailing, created by direct marketing agency Draft London, is being sent to 60,000 existing and prospective customers.
Enclosed are cards featuring illustrations used by psychologists for assessing visual perception. The first three feature optical illusions, including an image resembling both a vase and two faces, while a fourth carries an illustration of a Saab 9-3 1.9 TiD in a similar style.
The mailing uses the strapline "Change the way you look at diesels".
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