Winston, a rescued boxer dog from Oklahoma, has a universal blood type.
So he's become a regular blood donor for other doggies who need help.
Whether they were in an accident and lost blood or just need an extra transfusion during surgery, Winston's blood can help.
His family adopted him when he was burned by acid, starving and abandoned.
They immediately all fell in love. Such a cute story!
Check out the video (above) to meet Winston and see just one of the lives he's saved.