In most cases, each product contains some of the functions of the other product(s).
For example, many Travel Insurance and Travel Medical Insurance plans contain provisions that might seem to over lap. Both generally (but not always) provide emergency transportation, via ground ambulance, and some cases Air Ambulance. The difference between these and an actual Air Ambulance Service is that the previous mentioned plans usually guarantee transportation to the “nearest” medical facility (hospital/clinic) while the Air Ambulance guarantees transportation to the nearest medical facility, and then back home to your “Home Hospital” in the country where you are from. Huge difference! (Note: Most Air Ambulance services are not insurance, and thus not guaranteed! In addition, service is not available worldwide but many provide service in all of North America, including Mexico, as well as the Caribbean)
Travel Insurance generally insures your financial investment in your trip. Such as the cost of lost luggage, cancelled flights, or the non-refundable loss of tour costs associated with a cancellation due to an acute onset of a medical condition, injury or death, but it may not cover costs of medical attention needed abroad.
Travel Medical Insurance covers costs of needed medical attention when traveling abroad. Note that U.S. medical insurance is generally not accepted outside of the U.S. Medicare and Medicaid is also not provided or accepted outside of the U.S. This coverage is generally available by the day, week, month or year, and is usually (dependent upon age) very reasonable in costs from about $3.00 USD$ a day, and less if 30 days or more is purchased.