Apparently, there is no such prison… and the recipients appear to be in the same area as the return address, so people on the mailing list may recognize that it may be something of a hoax. It is pretty certain that this envelope gets opened and the enclosed, testimonial letter (shown below) gets read. Because the topic is security-related and the message is humorous, the idea probably works in this context.
Direct Mail Piece from Fake Sender – Star Protection
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