The American Red Cross is encouraging people to add a new holiday tradition to their list this year in the form of its “Spread cheer with a blood or platelet donation.”

To mix with the Christmas cheer and to celebrate the 20th anniversary of the film “Elf,” all who come to donate blood through Nov. 30 will receive an exclusive pair of “Elf” + Red Cross socks while supplies last.

Donations are critical to the blood supply as the holiday season draws near — a time when blood donations often decline, the organization said. Donors of all blood types are urged to give, especially type O blood donors and those giving platelets, according to American Red Cross.

For more details, visit RedCrossBlood.org/Elf.