'Shark Tank': Mark Cuban invested 6 figures in a company that went from a $600 side hustle to over $3 million in sales in just two years

Mad Rabbit Tattoo founders on ABC's "Shark Tank."

Oliver Zak and Selom Agbitor started Mad Rabbit Tattoo, a company that sells tattoo aftercare products, as a side hustle while attending Miami University in 2019. Now, that side hustle has landed the pair of entrepreneurs a six-figure investment from billionaire "Shark Tank" star Mark Cuban.

"We started with $300 each [in January 2019]," Zak said during Friday's episode of ABC's "Shark Tank," "and we were lucky enough to be profitable from week one."

Zak and Agbitor made Mad Rabbit's first balm (which moisturizes tattooed skin to prevent discoloration) in a crockpot in their college kitchen with ingredients bought off of Amazon.

"We've grown a lot" since then, Agbitor said on "Shark Tank."

In their first year, Mad Rabbit sold $400,000 worth of products like body balms, gels and sunscreens. In 2020, sales hit $3 million, they said.

That rapid sales growth is why the co-founders told the Sharks that Mad Rabbit would be worth a $500,000 investment for 5% equity (which would have given the company a $10 million valuation).

Mad Rabbit products range in price, from $15.99 for tattoo balm to $29.99 for sunscreen or "soothing gel," according to the company's website. It also offers a subscription service, from $11.99 to $22.49, where customers can choose to receive a product every one to three months.

"Tattoos require constant maintenance and upkeep to continue looking healthy," Zak said. "With that in mind, Mad Rabbit was formulated with all-natural ingredients to keep tattoos looking vibrant and prevent ink discoloration."

At the time of filming, the duo had over 5,000 subscribers, Agbitor said.

The company's growth impressed the Sharks, especially after Zak and Agbitor shared that they'd achieved this success while still working full-time jobs outside of Mad Rabbit. (Zak said he worked in consulting and Agbitor worked in finance.)

"I have a lot of respect for you dudes," Kevin O'Leary said on the show. "You're not even full-time yet, and you're killing it."

Mark Cuban was also intrigued by the duo.

"I like what you guys are doing," Cuban said before offering them a $500,000 investment for 12% equity in Mad Rabbit — an amount of equity he called "non-negotiable." Zak and Agbitor accepted the deal, which values their company at nearly $4.2 million.

"I know my parents are going to be really happy," said Agbitor, who was born in Ghana, but grew up in Ohio. "I'm going to be an inspiration to my friends back home in Ghana."

Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank."

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