spyhole
A spyhole, also known as a peephole or a door viewer, is a small optical device, typically a wide-angle lens, installed in a door. Its primary function is to allow someone inside a room or building to see who is on the other side without opening the door. This enhances security by enabling a person to identify visitors before granting them entry, thus preventing unwanted or potentially dangerous encounters.
Spyholes are commonly found in residential doors, hotel room doors, and other entryways where security is a
The typical installation involves drilling a hole of appropriate diameter through the door at eye level for