The highly rated Prime-Line Products U 10313 peephole-door viewer is constructed of a solid brass housing, and it comes in a classic bronze finish. It can easily be installed on doors ranging anywhere from 1-3/8 in to 2-1/8 in thickness, with a 9/16 in diameter hole that is required for installment.
You only get one shot at drilling the installation hole, and if you mess it up, you will have to look at that mistake every time you leave, or enter your home. Rather than drilling completely through from one side of the door, partially attack it from both sides and meet in the middle. Click here for the Top 10 Best Peepholes and Door Viewers.
This is done to prevent some potentially ugly splintering of the wood that can occur when you punch through from one side.
The U 10313 door viewer was designed for one purpose, keeping you and your family safe from the dangers of home invasions and robberies. It is equally effective in nighttime low light situations as it is during the daytime with full outdoor lighting. The only thing preventing this model from receiving a five star rating is its lack of a peephole cover. All things considered it is a solid product offering, and a very good buy.