The difference between stock index futures if 1505 and if 1506 is that 1505 represents a contract that expires in May of 20 15, and if 1505 represents a contract that expires in June of 20 15, that is, the contract expiration dates are different.

The full name of stock index futures (SPIF) is stock index futures, which can also be called stock index futures and futures index. It refers to the standardized futures contract with the stock price index as the subject matter. The two parties agree to buy and sell the underlying index according to the size of the stock price index determined in advance at a future date, and settle the difference in cash after the expiration.