1, check the gun body, there is a safety button, and there is a long shaft behind the safety button.

2. There is a hook on the left side of the central circle of the spring, which is sleeved on the long shaft. The central circle of the spring is sleeved on the fixed shaft of the upper trigger, and the hook on the right side of the central circle of the spring is clamped on the rear half of the upper trigger.