This door viewer is constructed of a solid brass housing, and it comes in a satin nickel plated finish. The lens of this viewer is made of plastic and it features a 160 degree angle of view. This viewer can be installed on doors from 1-3/8 in. thick to 2-1/8 in. thick, with a required 1/2 in. diameter hole for installation of viewer. This door viewer is designed to help keep you safe when answering your door and is ideal for day or night viewing with adequate exterior lighting. This viewer is easy to install and it is used by many. As an available option, inside viewer covers (sold separately - not included with this item) prevent reversed visibility through door viewers from the exterior of the home, increasing the security and privacy of your home.