MATERIAL:The doorbell holder is made of plastic shell and steel. It's tight and so your doorbell won't fall off your door. All holes in the doorbell cover are carefully designed not to block the doorbell motion sensor and two-way audio..No Tools or Installation Required: Attaches securely in seconds and easily installs and uninstalls. Simply place the video doorbell inside and slide it over your front door, then adjust the fixed clip according to your door thickness..Compatible Doorbells:The anti theft doorbell mount is compatible with most video doorbell including Video Doorbell 1/2/3/3 Plus/4 and Video Doorbell (2020 Release). The maximum size of video doorbell can be placed inside is 2.55" wide 5.11" high 1.14" thick..Compatible Door: Suitable for most kind of door. The thickness of the door must be between 0.59 inches and 2.36 inches. You can measuring your door thickness before order. It can be used for doors that open left or right.(Doors that must be opened inward!). Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.