The Red Cross is trying to encourage more Americans to donate blood, especially in the summer, which is usually a slower time.
They're dramatizing the need for blood with missing letters - A, B, and O - the major blood types.
From big brands like Domino's pizza to average people, they're removing those letters to show how important even one letter can be, and how every unit of blood counts.
The Red Cross says only 3 percent of eligible Americans actually donate.
"Thousands of pints every single day are needed throughout the country to keep hospital patients alive. that's why we need people who've never donated blood before, or those who haven't donated in a long time, to come out and give the gift of life," says Cliff Numark, the vice president for biomedical services of the Red Cross.
Every two seconds in the US, someone needs a blood transfusion, so having enough supply is vital.
The "Missing Types" blood drive continues through Sunday.
To find a time or place to donate, just follow this link : Give Blood.
Red Cross 'missing types' drive for more blood donors