“Open Your Hand And Smile” has been an advertising slogan associated with M&M's. The phrase captures the brand's classic visual of opening a palm to reveal colorful chocolate candies, often alongside the better-known promise that M&M's melt in your mouth, not in your hand.
M&M's were introduced in the United States in 1941 by Forrest Mars and Bruce Murrie. Their hard sugar shells were designed to protect the chocolate, making the candies easier to carry in warm conditions. That practical feature became the foundation of the brand's long-running advertising message.
The brand has used several slogans and campaign lines over the decades, including “Melts in your mouth, not in your hands,” “The milk chocolate melts in your mouth, not in your hand,” and “Have a handful of smiles.” “Open Your Hand And Smile” belongs to that broader family of hand-and-smile advertising imagery rather than replacing the best-known product slogan.
A common mix-up is remembering only the melting slogan and overlooking shorter campaign phrases used in individual commercials. The question asks which product used this specific ad line, making M&M's the canonical answer.