They are punch through holes. The normal map can be used for creating punch through effect of papers, card boards or creating bullet shots.

These holes go inwards. This texture can also be used together with "Imperfection and Decal of Bullet Holes (Imperfection 0003)" which goes outwards.

They are bullets holes. The most useful maps of this texture are normal and mask. With the normal map, you can shoot holes in any materials especially metal. The mask tells you the position of the holes.

It is good to be treated as an imperfection or decal.

These holes go outwards. This texture can also be used together with "Decal of Punch Through Holes (Imperfection 0004)" which goes inwards.