That hole was caused by spall blow - out.

那个洞就是被碎片打穿的。

youdao

If bicycle pump, then the alignment hole - by-blow look at a better effect.

如有自行车打气筒，则对准小孔逐个吹一下效果更佳。

youdao

If bicycle pump, then the alignment hole - by-blow look at a better effect.

如有自行车打气筒，则对准小孔逐个吹一下效果更佳。

youdao