What are single-bag and double-bag door covers?

The difference between single bag and double bag of door cover lies in:

A single bread door cover means that only one side of the wall is covered with a door cover. For example, the balcony door is a single bread door cover, and there is only a door cover in the room! The balcony side is not included.

Double bread door covers mean that both sides of the wall should be wrapped, just like bedroom door covers. Both are two loaves of bread.

: 1, single bag door cover: entrance door, balcony door and door cover are only on the side you see. If the door has a middle, then both the inside and outside of the door should be covered, and both the inside and outside should be covered.

2, double door cover: for example, the room door, kitchen door and bathroom door can be seen on both sides, the door is on one side of the wall, and only one side behind the door is wrapped.