Genuine BMW roof bars. Cost over £170 from BMW !
BMW base support system.
Maximum permissible roof load: 75 kg. The base support arms are made of high-strength aluminium tubing.
(from BMW web page)
http://accessories.bmw.co.uk/internet_bmw/servlet/navigateDetails.do?language=en&nscId=1100&localePath=/UK/en&ts=1322317540085&from=2&fromList=tr