DBA's mid-series enhanced performance rotor features Thermal Stability Profiling for improved heat handling. Thermo-Graphic paint markings on the rotor allot for effective heat monitoring, when the painted lines change color you can see the temperature that the rotors have reached allowing you to accurately match the proper brake pad compound. The 4000 drilled rotors have a unique slot and drill design which allows for the gasses to escape that are trapped between the pad and the rotor, which ensures consistent contact. These key features make this a great rotor for street use, and the weekend warrior who demands the most out of their car on and off the track.