Swire Properties has sold a duplex apartment at the ultra-swanky Opus Hong Kong in Mid-Levels for HK$497 million, setting a record as Asia's most expensive flat. The 5,188 sq ft duplex flat A, on the ground and first floors of Opus Hong Kong at 53 Stubbs Road and including two car parking spaces, was sold yesterday at HK$95,971 per square foot, according to information on the website of the register of transactions of residential properties (first-hand sales). That breaks the previous record for price per square foot, set in April, when a company director with a Singaporean passport, Wang Shuang, paid HK$93,000 per square foot for a HK$433.8 million home on the 45th floor of 39 Conduit Road. The 4,664 sq ft property was in a Henderson Land development. The Opus duplex has 5,188 sq ft of saleable area and a 3,245 sq ft garden which is not included in the saleable area. It has a 36 sq ft balcony and 113 sq ft of verandah. The sale price represents a 4.25 per cent discount from the list price of HK$520 million on the development's website. The buyer was not disclosed. The register website showed the buyer chose a 90-day payment option to enjoy the special discount, including the cash benefit and ad valorem stamp duty. Opus, a 12-storey super- deluxe property completed in 2012, is dubbed Hong Kong's most expensive apartment block. It is Canadian-American architect Frank Gehry's first residential building in Asia and features an unusual twisted shape. Each unit has floor-to-ceiling windows and commands 360-degree views of Victoria Harbour and Mount Cameron. The property is for sale and lease by Swire and has often set records for both. In December 2012, a tenant who had agreed to pay a monthly rent of HK$850,000 for a 6,000 sq ft duplex unit at Opus pulled out after government measures cooled demand for property. British consul-general Caroline Wilson moved into the entire third floor in 2013. The British consulate refused to disclose the rent. The register records show a flat on the second floor of Opus was sold by Swire in May this year for HK$368.64 million. A flat on the 10th floor sold in September for HK$451.30 million and one on the 11th floor sold in June last year for HK$430 million.