McDonald's unveils new straw to drink two shake flavors at once

CHICAGO, IL -- McDonald's has just unveiled its latest product, but you can't eat it.

A new advertising campaign is promoting a straw that lets you sip two flavors of a shake at once.

McDonald's said a whole team of engineers designed the new straw.

PUTTING 'THE STRAW' TO THE TEST

Patricia Lopez puts 'The Straw' to the test

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It was created for the shamrock shake - which has a layer of chocolate on the bottom and mint on the top, so you need "the straw" to taste both flavors.

"The straw" debuted on Facebook Live Wednesday.