两个四号就是紧急弹出孔，关机状态下用小针插进4号1.5厘米深度，前方对应方向的槽位就可以直接拿出来了
To manually release magazines, insert the end of a small metal pin or straightened paper clip
into the appropriate magazine access hole at the back of the device about 1.5 cm (0.6 inch),
while another person grasps the magazines on that side and pulls them out of the front of the
unit. For the MSL4048, MSL8048, and MSL8096, all magazines on a side are released and
should be removed at the same time
