CHICAGO (CBS) — Head to Manny’s Deli for a free sandwich on Tuesday – but don’t forget your mask.

The free food started as a challenge. A couple of weeks ago on Twitter, Manny’s Cafeteria & Delicatessen – 1141 S. Jefferson St. – said if they could go 30-days without having to tell a customer to wear a mask properly, they would host a day of free sandwiches.

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That did not work out.

But an anonymous donor stepped in, and on Tuesday, Manny’s will be handing out up to 1,000 free sandwiches to anyone wearing a mask – correctly.

The sandwiches will be handed out on a first-come, first-serve basis. Doors open at 9 a.m.

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The donor is also paying for free sandwiches for workers at the United Center mass vaccination site.

CBS 2 Chicago Staff