An electric device comprising: • a support frame which is intended to be fixed to a wall and which is provided with an internal perimeter which delimits an opening which is intended to receive at least one electric module, the internal perimeter comprising an upper side and a lower side opposite the upper side, • at least one electric module comprising a main body which is provided with an upper face, a lower face opposite the upper face and a front face which extends between the upper face and the lower face in a first direction and which is intended to be directed at the opposite side in relation to a wall when the electric module is received in the opening and the support frame is fixed to the wall, • an engagement device for locking the main body to the support frame when the electric module is received in the opening, wherein the engagement device comprises: • a pair of projections (16; 17) which extend from one side between the upper side and the lower side of the internal perimeter towards the other side between the upper side and the lower side, the projections being spaced apart from each other so as to delimit, with a portion of the support frame which extends from one of the projections to the other, a seat which is intended to receive a connection portion of an engagement element, • wherein the engagement element comprises the connection portion which is formed to be received in the seat, and wherein the engagement element is resiliently secured to one face between the upper face and the lower face of the electric module so as to be movable between an expanded configuration, in which the electric module is locked to the support frame by means of interference between the support frame and the engagement element when the connection portion is received in the seat, and a retracted configuration, in which the electric module can be removed from the support frame, and • a pair of abutment surfaces which belong to the face of the electric module which is provided with the engagement element, the pair of abutment surfaces extending one opposite the other with respect to the engagement element so as to act as a guide for respective projections of the engagement device for the insertion of the connection portion in the seat, wherein the engagement element extends longitudinally from a first end thereof, which is placed at an intermediate portion of the face of the electric module provided with the engagement element, towards the front face of the electric module, terminating in the connection portion, wherein the first protrusion extends between the first end of the engagement element and the connection portion, characterized in that the engagement element comprises, in the region of a free end of the connection portion which is directed towards the front face of the electric module, a second protrusion which extends in the first direction. • a support frame which is intended to be fixed to a wall and which is provided with an internal perimeter which delimits an opening which is intended to receive at least one electric module, the internal perimeter comprising an upper side and a lower side opposite the upper side, • at least one electric module comprising a main body which is provided with an upper face, a lower face opposite the upper face and a front face which extends between the upper face and the lower face in a first direction and which is intended to be directed at the opposite side in relation to a wall when the electric module is received in the opening and the support frame is fixed to the wall, • an engagement device for locking the main body to the support frame when the electric module is received in the opening, • a pair of projections (16; 17) which extend from one side between the upper side and the lower side of the internal perimeter towards the other side between the upper side and the lower side, the projections being spaced apart from each other so as to delimit, with a portion of the support frame which extends from one of the projections to the other, a seat which is intended to receive a connection portion of an engagement element, • wherein the engagement element comprises the connection portion which is formed to be received in the seat, and wherein the engagement element is resiliently secured to one face between the upper face and the lower face of the electric module so as to be movable between an expanded configuration, in which the electric module is locked to the support frame by means of interference between the support frame and the engagement element when the connection portion is received in the seat, and a retracted configuration, in which the electric module can be removed from the support frame, and • a pair of abutment surfaces which belong to the face of the electric module which is provided with the engagement element, the pair of abutment surfaces extending one opposite the other with respect to the engagement element so as to act as a guide for respective projections of the engagement device for the insertion of the connection portion in the seat, wherein the engagement element extends longitudinally from a first end thereof, which is placed at an intermediate portion of the face of the electric module provided with the engagement element, towards the front face of the electric module, terminating in the connection portion, wherein the first protrusion extends between the first end of the engagement element and the connection portion, characterized in that the engagement element comprises, in the region of a free end of the connection portion which is directed towards the front face of the electric module, a second protrusion which extends in the first direction.