China's stock index futures closed higher on Friday, with the contract for April, the most actively traded, up 0.5 percent from the previous trading day to 2,625.8 points. The May contract gained 0.51 percent to 2,628.6 points. The June contract climbed 0.57 percent to 2,628 points, while the September contract was up 0.63 percent to 2,633.4 points. The stock-index contracts, agreements to buy or sell the Hushen 300 Index at a preset value on an agreed date, are designed to allow investors to bet on and profit from both gains and declines in the market. The index futures was launched at the China Financial Futures Exchange (CFFEX) and started trading from April 16, 2010. The CFFEX has set the base value for all the four contracts at 3,399 points.