Slug (coin)

Honest customers may also suffer losses when change returned for overpayment is in the form of a slug rather than a genuine coin.

Customer losses may be either unintentional on the part of merchants (such as when perpetrated by unwitting cashiers or machines designed to automatically process previous payments as change for later customers) or the result of the deliberate substitution of genuine coinage by corrupt cashiers and vending machine operators.

Some slugs that are made to match the face details may not be immediately recognizable as such to handlers, and may enter circulation.

Older, cheaper, and other low-tech machines that have fewer security measures are more likely to be defrauded by slug users.

As an example, the fully mechanical mechanisms used in the traditional type of small vending machines that distribute candy or toys, and that can still often be found today at the entrances and/or exits of grocery stores and other retailers, can be fooled by cardboard coins.