Door Viewer is a revolutionary new security device that can be easily installed in wood, fiberglass, or metal doors. It is designed to replace the standard peephole and give you the peace of mind of clearly seeing who is visiting. Unlike a conventional peephole, you can stand up to 2-3m back from the door to safely see out. Utilizing prism optics, the Door Viewer projects the outside image onto the view screen while maintaining your privacy and protection. You can see clearly out while visitors cannot see in. Children and those in wheelchairs love the Door Viewer since they can see out without having to reach up to a peephole, alerting others of their presence.  Specifications: 6050---60mm is the diameter of hole in the door for door viewer; 50mm is the diameter of the viewing range of door viewer,used in the door of 50mm thickness.Characteristics: a) Optical systems adopt complete optical lens and you can get clear and stable imageb) Visual angle may reach 120° for easy obser