Although we carry the most common types of bottom garage door seals (vinyl and rubber) and the aluminum retainers that hold them, keep in mind that some seals are specific to the brand and model door you may have.
If you can e-mail us with pictures of your door and gap, or bring in some pictures, we can offer you our opinion.
Keep in mind that these seals will help with some variance in your floor levels, but if the slope is too severe, you may have to fix the concrete to get a good seal.