McDonald’s are really going in hard on the 50th anniversary of the Big Mac, having in the past few weeks given away 300,000 free burgers across Australia, as well as launching an even bigger Big Mac.

Now they are releasing the rarest of all Macca’s collectables — no, not those Muppet babies toys, everyone had those — but bottles of their special sauce.

The bad news is it isn’t widely available, but instead can be won in an eBay auction. The good news is the money goes to charity. The other good news is it comes with a McDonald’s mini-fridge.

“Continuing the celebration of the iconic Big Mac, Macca’s fans can bid to win a limited edition Big Mac mini fridge filled with three 500ml bottles of Special Sauce,” reads the listing.

“Available exclusively to Australians, this eBay charity auction will donate all funds raised to Ronald McDonald House Charities.

“Aussies who want to be in with the chance to take home the mini fridge that features a Big Mac pictogram wrap, and the first three bottles of Macca’s 2018 release of the sauce, will need to place your bids here before 10am Wednesday 6 June 2018.”

Bids are currently at $3,650.

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