Wall box system, flexible and elastic wall cover and electrical wall box

A wall box system, a flexible and resilient wall cover, and an electrical wall box for preventing air from entering the wall box from a wall cavity, the wall box system comprising: a housing having an interior space defined by a circumferential wall, a rear cover, and a flange; a plurality of glands, each of the plurality of glands being inserted into a corresponding one of the plurality of holes of the rear cover to seal the holes and prevent air from intruding into an internal space of the housing; each gland in the plurality of glands comprises a side wall, an open end and a closed end; and each of the plurality of glands is formed of an elastic material having a first thickness; the closed end of each of the plurality of glands includes a membrane portion having a second thickness less than the first thickness for receiving a permeate and a bi-directional pathway of an electrical conductor, and the elastic material forming the gland remains in contact with an outer surface of the electrical conductor, the