So, before buying an intercom, decide where it will be used: at home, in the office, in a closed facility. After all, depending on this, you need to choose a model with the appropriate functionality.

We note the main criteria that you need to go through before buying an intercom:

Audio or video intercom. The first is capable of transmitting only the voice of the visitor, and the second - the voice and image. For home or office use, an audio intercom is enough: with a small number of visitors, you can easily recognize them by voice, but you can save a lot of money, because such a device costs an order of magnitude cheaper. Although if the budget allows and you want to get more amenities, you can take a video model. For closed facilities, only the second option is suitable, since there the guards must clearly see who is standing in front of the entrance to the building.

Display. If you stopped at a video intercom, then next you need to decide on the screen size. The minimum diagonal is 3.5 inches, but this is very small, since even smartphones have a larger display. Accordingly, it will not be easy to understand who came. For apartments and offices, models with displays from 7 inches are suitable. If you want to get a clear and detailed image, then choose a video intercom with a screen of 10 inches or more.

Communication method. There are 2 options to choose from: loudspeaker or handset. In the first case, you need to press a button on the case, after which you can communicate with the visitor. And in the second case, the conversation begins after picking up the handset. With a large flow of visitors, a loudspeaker will be preferable, since it requires less effort. Although it all depends on the individual preferences of the owner.

Memory block. Devices that have it are able to automatically take photos of people who came in your absence. The data is stored in memory and can then be copied to a PC. The option is convenient, but intercoms with a memory unit are quite expensive. Whether you need it or not - decide for yourself.
Number of channels. This parameter determines how many call panels or additional equipment you can connect to the intercom. An intercom with a large number of channels is suitable for a private house or a large facility where you need to control several entrances. In other cases, 1 channel is enough.

Lock control method. Locks are electromechanical and electromagnetic. The latter are considered more convenient, as they are quiet and inconspicuous.

Other parameters (body material, color, shape) do not affect the functionality of the intercom. Here, everyone chooses based on personal preferences, so there are no universal recommendations here.  Choose outdoor intercom system from the best manufacturers and do not skimp on the safety of your home