Quick! Ugg Just Restocked the Impossible-to-Find Ultra Mini Boots in 4 New Colors

If there's ever been a time to act fast, it's now, because Hollywood's favorite Ugg boots are back and better than ever thanks, in part, to a collaboration with mental health-conscious fashion brand Madhappy.

Whether you've realized it or not, the Ultra Mini boot has become the it-girl shoe for models like Bella Hadid (take her boxer-briefs moment, for example) and actresses like Jennifer Garner and Keke Palmer, who kept comfortable in a pair during New York Fashion Week. And after multiple sellouts, the elusive boots are back in stock with a few extra details.

"We have been fans of Ugg for years prior to starting Madhappy," Noah Raf, co-founder and chief creative officer at Madhappy tells PEOPLE. "What they've been able to create — both in terms of the quality and craftsmanship of their products, but also in terms of brand narrative and equity — is admirable. With our collective identities and shared values, we knew that a collaboration between the brands made sense."

Ugg x Madhappy Classic Ultra Mini Boots

• Ugg x Madhappy Classic Ultra Mini in Sand, $160; madhappy.com
• Ugg x Madhappy Classic Ultra Mini in Nuit, $160; madhappy.com
• Ugg x Madhappy Classic Ultra Mini in Petal, $160; madhappy.com
• Ugg x Madhappy Classic Ultra Mini in Calm, $160; madhappy.com
• Ugg x Madhappy Classic Ultra Mini in Chestnut, $160; madhappy.com

These limited-edition mini boots are available in five shades, with four of them being inspired by the neutral color palette of Madhappy's Spring Classics Collection — Sand (light neutral), Nuit (navy gray), Petal (light pink), Calm (sky blue) and the original Ugg Chestnut, of course.

Buy It! Ugg x Madhappy Classic Ultra Mini, $160; madhappy.com

But this collection is about so much more than celebrity-loved styles and pastel hues. Madhappy's brand mission is to drive the conversation surrounding mental health, inspiring its collective community "to see softness as a superpower," according to a press release.

However, this isn't to say that the brand didn't take steps to differentiate these Ugg boots from the traditional classic minis. "We injected key elements of our brand into the iconic Ugg silhouette. Most notably, our Classic Ultra Minis incorporate Madhappy's signature hood stitch across the body," Raf tells PEOPLE. "Our boot also updates the silhouette with a lower shaft height for easy on-off and versatility."

Raf explains that the brand has a longstanding admiration of Ugg's original shoe design and wanted to pay homage while also intertwining new details that provide "a fresh take on the silhouette." As a little token of this, there is a little peace sign (a signature of the brand) embossed into every pair.

Buy It! Ugg x Madhappy Classic Ultra Mini, $160; madhappy.com

Though these boots are the lovechild of Madhappy and Ugg, they still consist of everything shoppers know and love about the iconic Classic Boot. Each pair is artfully crafted with a soft suede upper, a cozy, upcycled wool blend interior, and a featherweight outsole made with Ugg's Treadlite technology that makes these shoes both indoor- and outdoor-friendly — just with the addition of Madhappy's signature hood stitching, peace sign, and embossed name.

You can officially shop the Ugg x Madhappy collection at both Ugg and Madhappy sites, but act fast if you want a chance to grab the latest collaboration from these cozy-cool brands.

Buy It! Ugg x Madhappy Classic Ultra Mini in Sand, $160; madhappy.com

Buy It! Ugg x Madhappy Classic Ultra Mini in Nuit, $160; madhappy.com

Buy It! Ugg x Madhappy Classic Ultra Mini in Petal, $160; madhappy.com

Buy It! Ugg x Madhappy Classic Ultra Mini in Calm, $160; madhappy.com

Buy It! Ugg x Madhappy Classic Ultra Mini in Chestnut, $160; madhappy.com

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