Don’t overlook this coverage because of its name, which correlates to its historical roots when goods were largely transported by ship.
It evolved to cover cargo and equipment being transported on land, and today covers business property that is mobile in nature as well as special-equipment items generally excluded from standard business property policies. (For example high-dollar technology equipment or custom-made equipment.)
Some Inland Marine policies will cover insured property no matter where it's located, offering protection for all perils, including mechanical breakdown.