It’s the promotion that went viral on TikTok last year, with more than 40 million views on the hashtag #frankgreenluckybag.

Now, cult water bottle brand Frank Green’s Lucky Bag promotion is back for the second year, giving shoppers the chance to win $50,000.

To take part in the Lucky Bag promotion, all you need to do is purchase one of two Lucky Bags.

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There are two specially curated Lucky Bags available to buy: one costs $89.95 with a minimum value of $150 Frank Green products, and the other costs $119.95 (with a minimum value of $200).

And if you shop the Lucky Bag deal, you’ll automatically go into the running to win a $50,000 cash prize.

So how does Frank Green’s Lucky Bag promotion work?

When you buy your ‘bag’ for either $89.95 or $119.95, you’ll receive a mystery assortment of famous Frank Green products — which will only be revealed at the moment of unboxing.

Possible items you could get include coloured drink bottles that are both large and small, coffee cups, stylish lunchboxes and dog bowls.

If last year’s success is anything to go by, fans of the brand will want to get in quickly as the Lucky Bags are expected to sell out.

Founder and CEO Benjamin Young said in a statement to Best Picks: “We want to bring joy to our consumers and surprise them like never before.

“We truly feel lucky to have the awesome community that we do.

“They are such brand fans so the decision to give away a huge $50K cash prize is about giving back to one of these loyal fans which ultimately will be life changing.”

Benjamin added: “Lucky Bag is an irresistible way to start or continue one’s reusable journey and what better way to start a new journey than with $50K cash in your hands”.

The challenge is already going viral on social media, with thousands of shoppers in a rush to snap up the Frank Green bags.

“Omg, this is awesome,” wrote one on Instagram.

Others have shown off the haul they received in their Lucky Bag.

For more information, terms and conditions and to shop the Lucky Bag giveaway, head here now.