Striped Sunflower Seed
Good for larger birds like Blue Jays and larger. Smaller birds tend to find this seed difficult/impossible to break open so its not universal to the songbirds like black oil sunflower seed which is smaller and easier to open.
This is a great seed to put out if you are inundated with Starlings. They cannot crack it open. It's a great seed to use strategically to continue to feed larger birds without encouraging Starlings who are invasive and compete for resources with native birds.