EDISON - Slurpee machines across the country were humming Thursday as 7-Eleven gave out free drinks for 7-Eleven Day.

The convenience store chain does the promotion every year on July 11 (7/11) between 11 a.m. and 7 p.m.

The frozen carbonated drink is sold exclusively at the chain. 7-Eleven estimated that 9 million Slurpees would be given out Thursday.

7-Eleven has been selling Slurpees since 1965 after the success of the similar ICEE drink