HD LENS: HD Optical Glass Lens Offers 220 Degree Crystal Clear Panoramic View an Extraordinary Wide Angle Coverage.It covers the area from the porch ceiling to the doormat, extending to both sides of the doorway across the street. It offers the highest quality security for you and your family PRIVACY COVER: Heavy Duty Privacy Cover Provides Top Privacy and Security-With the cover in place, no one from outside can see through the viewer into your home even with the reverse peephole.You can open and close the heavy duty back cover flexibly and smoothly. It allows you to identify visitors from a locked door, offering the highest level of privacy for your protection and safety HASSLE FREE INSTALLATION: The door viewer is made of durable solid brass metal comes with matched drill bit (Φ 28 mm), with Super Simple Installation. Suitable for 1 21/32" to 2 1/8" (42mm-54mm) thick doors, simply drill a suitably positioned 1 7/64″(28mm)diameter hole, insert the viewer into the hole then screw the two sides together and tighten by hand WIDED USED: Built to Last Construction, The door viewer gives a lifetime of durability. It comes in multiple finishes with sleek contemporary design to match your existing hardware and decor, blending in perfectly with various doors. A must safety complement for home, office, hotel and anywhere you need to view who is outside your door before opening AFTER SALES: If you are not satisfied with the purchase, we guarantee you a 100% refund or a replacement. We never stop improving our products and service to meet your complete needs.Please feel free to contact us, we are ready to solve all problem for you Peep holes for door are a common safety feature that allows people to see who is outside their door before opening it. They are usually installed at eye level and come in different sizes and materials such as glass, plastic, or metal. Peep holes can provide a sense of security and peace of mind, especially for those living alone or in areas with high crime rates. It's important to ensure that the peep hole is installed correctly and regularly maintained to ensure its effectiveness.In addition to the traditional peep holes, there are now digital peep holes that use cameras and screens to display a live feed of the outside. These can be particularly useful for those with limited mobility, as they can see who is at the door without having to physically approach it. However, it's important to consider the potential privacy concerns that come with such technology. Regardless of the type of peep hole, it's always a good idea to exercise caution when opening the door to strangers and to never feel obligated to do so if you feel uncomfortable or unsafe.