Plastic molded parts will occasionally have slight hairlines where the mold sides meet (This is called a Mold Seam or Flow line). This can look like a crack on a plastic component, but is only a slight visual detail on the top that does not compromise the integrity of the plastic.
Below is an example of a Mold Seam in one of our covers due to this effect.
Here is a rear view of the part where the seam is raised, thus confirming it is merely a minor visual effect and is still weatherproof.
If by any chance you had a drop/shock event and see a crack, contact our team immediately and add a couple of pictures