A liquid is degassed with an apparatus including a membrane contactor, where the liquid is drawn through the apparatus by gravity. The belt unit includes a belt unit main frame, a first roller, a second roller, a belt, a belt unit side frame, a handle part, a first contacted part, and a second contacted part. The housing includes a cover to close the housing interior and a mounting flange for mounting the housing to the vehicle side wall. A Home Phone Line Network Alliance system includes a telephone line network and a plurality of devices couple to the telephone line network.