A device with a large surface area designed to heat the air near it by conduction is a radiator.

Here's why:

* Conduction: Heat transfer through direct contact between objects of different temperatures.

* Large surface area: This maximizes the contact area between the radiator and the air, allowing for more efficient heat transfer.

Examples:

* Car radiators: They use a large surface area to transfer heat from the engine coolant to the air passing through them.

* Space heaters: Some space heaters use metal fins to increase their surface area and heat the air more effectively.

Let me know if you have any other questions!