This lens gives your OpenMV Cam the ability to see a wider field-of-view (FOV). The standard lens that ships with your OpenMV Cam has a 115° FOV which is good, but, not great for security applications. This lens has a 185° FOV so your OpenMV Cam can literally see behind itself.
Applications

The Ultra Wide Angle Lens is great for security applications where you want to see a wide field-of-view. For example, by using the Ultra Wide Angle Lens your OpenMV Cam can easily detect motion in an entire room using frame differentiating without having to be mounted far away.