When Bruce Wayne reestablished his connections to his father’s company, Wayne Enterprises, Bruce meets former board member Lucius Fox in the Applied Sciences Division. There, Bruce was able to acquire various gadgets for his soon-to-be alter ego known as Batman. One of them was the Tumbler, a prototype armored tank designed as a bridging vehicle for the military, includes weaponry and the ability to boost into a rampless jump.
The Tumbler has a pair of machine guns mounted in the nose of the car between the front wheels. In “Attack” mode, the driver’s seat moves to the center of the car, and the driver is repositioned to lie face-down with his head in the center section between the front wheels. This serves two main purposes: first, it provides more substantial protection with the driver shielded by multiple layers of armor plating. Second, the low-down, centralized driving position makes extreme precision maneuvers easier to perform, while lying prone reduces the risk of injury a driver faces when making these maneuvers.
“So what do you think?”
“Does it come in black?”
―Lucius Fox and Bruce Wayne
Source: Batman Wiki