Even though the Big Mac hamburger was first introduced to the public in 1967, it was sold in McDonald’s restaurants around the country only in 1968, and the fast food chain is celebrating the 50th year of the well-known burger’s existence with the launch of a limited edition “currency” it is calling MacCoin. It is not another cryptocurrency, but instead a token that can be collected, or used at the chain’s outlets to get a free Big Mac in exchange.

In an announcement Sunday, the company said it would distribute 6.2 million MacCoins around the world in over 50 countries, including at 14,000 restaurants in the United States. Starting Aug.2, customers would receive a MacCoin with the purchase of every Big Mac while stocks of the coins last. If you get a MacCoin and want to exchange it for another Big Mac, you can start doing that from Aug. 3, any time till the end of 2018.

You may want to collect them instead, since McDonald’s is producing the MacCoins in five different designs, one each to reflect the five decades the Big Mac has been around, the company’s statement said.

“The MacCoin highlights the ‘70s, showcasing the decade’s flower power, and the ‘80s alludes to pop art. Bold, abstract shapes defined the ‘90s and translate on the MacCoin design, and the early ‘00s specifically focuses on the technology that was at the forefront of the turn of the century. The ‘10s MacCoin celebrates the past 10 years and calls attention to the evolution of communication. Additionally, the seven languages featured across the various designs represent many of the countries participating: Arabic, English, Indonesian, Mandarin, Portuguese, French and Spanish,” it said.

The giving out of MacCoins would be limited to one for one person on a single visit. The full list of countries participating in this promotion can be found on this page.

McDonald’s president and CEO Steve Easterbrook said: “Since it was introduced at a family-owned McDonald’s restaurant 50 years ago, the Big Mac has traversed the globe and is enjoyed in cities from Shanghai to Chicago, providing delicious, feel good moments to people all over the world. So we wanted a global celebration as unique as the burger itself. The MacCoin transcends currencies to commemorate our global iconic burger while giving customers all over the world a chance to enjoy a Big Mac on us.”

Even leaving aside the company’s praise of its hamburger and health concerns surrounding fast food that have affected the company’s business, the Big Mac has sealed its place in history. Since the ingredients used in the burger — two all-beef patties, special sauce, lettuce, cheese, pickles and onions on a sesame seed bun — are the same everywhere, the Economist magazine had created an economic index that used the price of the burger in various countries as a comparison of purchasing power of different currencies. That gave the company the idea for the MacCoin.

Nick Delligatti, fourth-generation McDonald’s owner-operator and great-grandson of Jim Delligatti, the inventor of the Big Mac, said in the statement: “August 2 would have been his 100th birthday, and I believe he would be very proud knowing his humble sandwich has made such a lasting impression that people all around the world can enjoy it wherever they find a McDonald’s.”