An apparatus according to one embodiment of the present disclosure comprises a first circuit board; a first connector provided on one face of the first circuit board; a second circuit board disposed on the one face of the first circuit board, and electrically connected to the first circuit board; a second connector provided on one face of the second circuit board, and engaged with the first connector to electrically connect the second circuit board to the first circuit board; a sealing member disposed between the first circuit board and the second circuit board to seal a space between the first connector and the second connector; and a coupling member coupling the first circuit board and the second circuit board to each other.