Gobstopper

Gobstoppers, known as jawbreakers in Canada and the United States, are a type of hard candy. They are usually round, and normally range from about 1 - 3 cm across; though in Canadian/US candy stores, some stores or stands in Europe and many theme parks, gobstoppers can sometimes be up to 8 cm in diameter. The candies are traditionally very hard, hence the descriptive name of jawbreaker.