CLIMATE-CONTROL air-conditioning is standard on the X5. The system automatically distributes air throughout the cabin to give the best possible heating/cooling effect and incorporates an automatic air recirculating function that co-operates according to the quality of ambient air. A microfilter prevents airborne contaminants from entering the cabin, while double-glazed side windows that assist in the maintaining of interior temperatures - and reduce external noise - are optionally available. A "climate comfort" windscreen able to reduce dash panel temperature by 10 degrees Celsius on hot days is also optionally available.