What type of policy adds coverage for specific events not originally included?

An add-on policy is designed to provide additional coverage for specific events or circumstances that are not included in the standard coverage of a primary insurance policy. This allows policyholders to customize their insurance to better suit their needs by including extra benefits or protections beyond the basic terms. Such policies are particularly useful for addressing specific risks that are relevant to the policyholder's situation.

In the context of insurance, comprehensive policies typically offer extensive coverage for a wide range of events, but do not specifically highlight the inclusion of additional events outside their core provisions. Exclusion policies focus on explicitly detailing what is not covered rather than expanding coverage. Supplemental policies are often used to provide extra benefits, usually in conjunction with another primary insurance policy, but they do not necessarily allow for the inclusion of tailored coverage for specific additional events. Therefore, the concept of an add-on policy most accurately describes the ability to enhance and customize coverage for particular situations.