The Frelan Hardware Spy Hole Viewer Polished Brass adds a useful security aspect to any door by enabling the user to see who is behind the door before opening it. It can be used on houses but is more commonly seen in apartment blocks or hotels where there are constantly lots of people moving around the building. It features a screwing mechanism which makes it simple to adjust to door sizes between 35-55mm. It provides a horizontal 180 degree view of the outside of the door. This viewer has a polished brass finish; perfect for traditional front doors. The spy hole is incredibly ...