automotive brake disc, also known as a brake rotor. This component is part of a vehicle's disc brake system, which works by using calipers to squeeze brake pads against the disc to create friction and slow the rotation of the wheel axle.
Key information about brake discs:

• They convert kinetic energy into heat energy to stop the vehicle.
• Disc brakes are favored for their efficiency and superior heat dissipation compared to drum brakes, which reduces brake fade.
• They are typically made of iron and affixed to the rotating axle spindle.
• The specific disc in the image appears to be a vented rotor (indicated by the thick cross-section) and has five bolt holes for mounting. 2 stucks