Design space: A high-end radiator for China Product: Sampux DB2006M oil-filled radiator Design: LKK Innovation Territory: China Sampux, a Chinese manufacturer of domestic heaters, wanted to produce a higher-value radiator that would appeal to China's increasingly deep-pocketed and design-aware middle classes. Market research company Euromonitor International estimates that by 2020 China's middle class will be 700m strong - where the middle class is defined as households with incomes of Rmb60,000-Rmb500,000 ($9,500-$79,400) a year. LKK Innovation, a Chinese product-design agency, created an oil-filled radiator that was better suited to modern minimalist decor than Sampux's existing ranges. Spheres were punched on to the heat-releasing surface to spread heat better than conventional vertical panels - allowing the radiator to be smaller than Sampux's other radiators yet produce the same amount of heat. The DB2006M is square instead of the standard rectangular shape. Black was seen as a stylish colour, as white can become dirty easily and turns grey or yellow with age. While Sampux's other radiators are sold for Rmb600 to Rmb700, the DB2006M retails at Rmb1,580. About 8,000 units have been sold since the product was launched in November.