Simply put, the fuse mechanism of US stocks means that when the stock market falls to a certain extent, the market will automatically stop trading for a period of time. Under normal circumstances, after the fuse mechanism of US stocks is triggered, US stocks need to be suspended for 15 minutes.

The US Stock Research Institute mentioned that the fuse mechanism of US stocks can also be called automatic stop mechanism, which is a measure taken by the exchange to suspend trading in order to control risks. |

The fuse mechanism of US stocks can be divided into three levels during trading hours in the United States.

The primary market fuse refers to the market falling to 7%;

The secondary market fuse refers to the market falling to13%;

The third-level market fuse means that the market falls to 20%.

During non-US trading hours, a 5% increase or decrease in the price of stock index futures will trigger the fuse mechanism.