Outdoor electrical enclosures can be found on most streets are usually house electrical circuitry allowing access to things such as electricity, broadband and cable television to all of the houses that have the correct hardware installed. If there's something wrong with your cable for example, it'll often be the case that there's something malfunctioning within the enclosure which has to be fixed.
They're made out of a variety of materials depending on who's paying for it, as well as its geographical location, but they're usually made out of stainless steel. This is to protect against both the environment as well as people who are trying to either break in or simply to damage it for whatever reason. You do sometimes find enclosures made of materials such as aluminum but these are quite rare and there's usually a specific reason as to why they're made out of this. Some families / people with very large houses with their own electrical enclosure choose for it to be made out of wood to keep the aesthetic style for example. But again, this instance and the one previous are quite rare and by no means the norm. It's definitely possible to purchase custom outdoor enclosures, but it's only in specific circumstances these are purchased.
If you're looking to buy some outdoor electrical enclosures the first thing you must do is pick the right size to fit the electrical circuitry, as well as picking a design that fits in with the decor but which will also stand up to someone trying to break in.