1。 Any trading mode with low fluctuation is a tool and channel for profit, and the ultimate goal of arbitrage mode design is to let more investors win more profits. 2。 The risk of arbitrage trading with limited risk and low spread is a limited futures trading model. Commodity spot has the cost of holding positions, and the price difference is difficult to break through the historical level. Generally, the price difference line can be determined according to the historical level of commodity prices, so that the price range is fixed and its risk is fixed accordingly. Arbitrage trading has the characteristics of hedging, which can be combined by scientific mathematical model, and an effective portfolio can reduce the risk well. 3。 The price difference is clear and the income is stable. The change of futures price is not only affected by spot price, but also by supply and demand and speculation in futures market. If the price fluctuates greatly, the price deviation will be great. The fluctuation between bear market and bull market is amazing, which requires investors' judgment.