SINCE its launch in 1968 the Big Mac has been a firm favourite for many from the McDonald's menu.
Today, as the fast food giant marks the 50th anniversary of their popular burger, they have revealed two special edition members who are about to join the Big Mac family.
For a limited period the 50-year-old Big Mac - which is made from two all-beef patties, special sauce, lettuce, cheese, pickles and onions, sandwiched between a three-piece sesame seed bun - will be known as the 'Birthday Burger' on McDonald's menus across the country.
It will also be joined by a Mac Jr, including all the same ingredients but at a slightly smaller size, with one less patty.
For the hungrier among us a Grand Big Mac will also be available, again with all the same ingredients but in a larger size.
The original, which was launched in the US in 1968 and was rolled out across British branches in 1974, became famous for its secret sauce.
The sauce was created by American McDonald's franchisee Jim Delligatti in Pennsylvania, who took two years to perfect the recipe.
Of its birthday celebrations, Steven Howells, Head of Marketing at McDonald's UK, said: "As an iconic McDonald's product, we are proud and excited to be celebrating 50 years of the legendary Big Mac and for the first time ever in the UK, introducing the two new sizes for a limited time."
If you're a Big Mac fan and fancy trying the special edition versions you'll have to grab one soon as they are only available from February 7 until March 20.