M&M’s may be an old brand, but it is not afraid to try new things. In recent years there have been several modern takes on the classic candy from 1941, including limited-edition flavors (cherry, mint crisp and raspberry), packages of all-green M&M’s, and M&M’s with customized messages and images that people can order through a Web site.

But the latest innovation, M&M’s Premiums, is a bigger departure. Mars Snackfood, which makes the candy, has changed not just one aspect of the M&M’s, but everything from the formulation to the packaging, price and flavor.

“We’ve actually changed the recipe of M&M’s as America and the world knows it,” said Ryan Bowling, a spokesman for Mars Snackfood U.S. “This is a whole new recipe, both visually and to its taste as well.”

The candies themselves are fatter and less uniform than traditional M&M’s. More radically, these M&M’s have no candy shell — just a shiny topcoat with a marbleized, almost metallic-looking finish in bright colors.

There are five flavors — mint chocolate, mocha, triple chocolate, raspberry almond and chocolate almond — sold in a 6-ounce package for $3.99. Instead of lying in a rectangular brown bag, M&M’s Premiums sit in an upright cardboard box with a clear window that shows off the candy.

M&M’s Premiums are already on store shelves, distributed to outlets where M&M’s are sold, including convenience stores, supermarkets and mass chains like Target and Wal-Mart.