(CNN)– Thursday, Nov. 13, is Starbucks’ annual Red Cup Day.

If you order from a list of handcrafted holiday beverages, you get a free, limited-edition 16-ounce reusable red cup.

The offer is available while supplies last at participating U.S. Starbucks locations.

But the giveaway could be affected by labor relations.

Starbucks Union members voted to approve a nationwide strike on red cup day unless a contract agreement is reached.

Starbucks Workers United didn’t say how many locations would be affected.

See Full Page