A form of pseudo-insurance covering theft, loss, or damage to a rental car. In most cases it is a complete waste of money. If you have auto insurance you're generally covered in a rental car. Many credit cards also offer supplemental insurance which cover people who do not have auto insurance and in some cases items not covered by normal auto insurance.

Most coverage has a $250.00 deductible per Accident.

They tend to have the obvious exclusions to coverage:
1) Use of vehicle in criminal acts
2) Forgery or other deciet when obtaining vehicle
3) War
4) Taking the vehicle any place besides a paved public road
5) Using the vehicle for hire