Standard equipment on the 328i models includes 16-inch wheels, heated side mirrors, rain-sensing wipers, automatic headlights, foglamps, 'leatherette' premium vinyl upholstery, automatic climate control and a 10-speaker sound system with CD player, HD radio and an auxiliary audio jack. The coupe comes with a sport-tuned suspension, while the convertible gets a power-retractable hardtop, an upgraded stereo and power front seats with driver memory. Both two-door 328i's get 17-inch wheels and adaptive xenon headlights. Standard safety equipment on the 2011 BMW 3 Series includes antilock disc brakes, stability control, front-seat side airbags and full-length side curtain airbags. The convertible lacks the side curtains, but the regular front side airbags extend up to head level and there are also pop-up rollover hoops. The stability control system integrates several features designed to improve braking performance, such as periodically wiping the brake rotors dry when the windshield wipers are in use and automatically snugging the pads to the rotors when the driver abruptly lifts off the throttle. BMW Assist Emergency telematics are optional..