· Description: 100% brand new. The lens will secure your home against burglary, intrusions and home invasion. With a lid of 1.5mm thickness, cover the lenses by manually rotating the lid to well protect your privacy. Fit for door thickness: 35mm to 55 mm/1.37-2.16inch, tube diameter: about 16mm/0.63inch.   · Specifications: Angle: 200 ° Color: Black Material: Pure copper+High-definition optical lenses Top diameter: 30mm/1.18inch Door diameter: 16mm/0.63inch Applicable door thickness: 35-55mm/1.37-2.16inch   · Package List: 1 x Door Viewer · How to Measure: Please take part the old door viewer at first and measure the size of hole; if there is no door viewer, please measure the thickness of door.   · How to Install: 1. Depart the door viewer into 2 parts. 2. Insert the lenses from the outside of door. 3. Insert the base from the inside. 4. Tighten slot by hands or with the help of screwdriver.   · Note: 1. Please allow 1-3mm/0.04-0.12 inch error due to manual measurement. Thanks for your understanding. 2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard.