'Moo Muffs': Woman's colourful creations go viral

Ear muffs for calves, to prevent frostbite, started in Milwaukee and has become a global sensation.

In Milwaukee, a team of four professional sewers sits hunched over their machines, cranking out 350 pairs of "Moo Muffs" a day.

Owner Holly Poads tells CNN she can't believe how quickly her business has grown.

After being featured on national news in the U.S., it didn't take long for her colourful creations to go viral.

Moo Muffs -- earmuffs for calves that help prevent frostbite -- are being sold around the world, with distributors in several U.S. states and one in Japan.

She's also working to secure business partners in Canada.

Now that arctic temperatures are settling in, Poads is gearing up for an active season.