BEIJING -- China's stock index futures closed mixed on Wednesday, with the contract for April, the most actively traded, up 0.02 percent to close at 2,233 points.

The May contract went up 0.07 percent to end at 2,231 points. The June contract edged up 0.04 percent to end at 2,215 points, while the September contract dropped 0.05 percent to close at 2,195.2 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 either gains or 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.