When you see this kind of mirror in a hotel or a fitting room, call the police immediately. It is a "double mirror" in any way.

Double mirror: There is no gap between fingers in the mirror.

Ordinary mirror: there is a gap between fingers in the mirror.

Double-sided mirror, also known as single-sided perspective glass, is made of ordinary glass by vacuum coating and chromium, aluminum or iridium film. This glass can reflect most of the projected light back. This kind of glass is installed in the car, so people can see the outside clearly when sitting in the car, but people outside the car can't see everything inside.

Matters needing attention in installing two-way mirror

Directionality: When installing, the reflecting surface of the transparent mirror should face the bright observation direction.

Lighting type: the lighting of the observed party should be evenly illuminated on the walls and furniture, and the lamp should not be directly illuminated or illuminated on the glass. The light on the observer's side should be dim, and it is recommended to use an opaque lampshade.