Developed by EHS Brann Cirencester, the mail pack includes a button-shaped envelope, which features the strapline "Is life a juggling act?".
Inside the button is a sample bag of Buttons and a leaflet inviting recipients to "take a moment to enjoy something simple".
The leaflet also shows some examples of different Cadbury Buttons pack varieties on offer.
Karen Trickett, group account director at EHS Brann, said: "The clean, uncluttered design style of the mailer is intended to reflect the core attributes of Cadbury Buttons by positioning the brand as a simple chocolate treat, which helps provide a lift for both adults and children leading hectic lives."
Buttons have traditionally been aimed at children, until they were relaunched earlier this year with new packaging designed to make the brand more accessible to adults.
Cadbury used data from the Jigsaw Consortium -- its joint venture with Kimberley Clark -- to select the households the mailer will go out to.
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