In a method and system for collecting data from remote terminal units using the Internet, each remote terminal unit is connected to an Internet-ready communication module having an Internet-like client running thereon. The door structure comprises two vertical frame elements and an upper hollow frame element mounted on the vertical elements and on upper edges of two or more glass plates and having a front aperture adapted to be used as an handle of the door flush with the front surface thereof, the upper hollow frame element being used as part of the ventilation system of the oven. The spring cage limits displacement of the tension spring and includes a compression spring that cushions the displacement of the tension spring. In another method, return margin of the tubular device adjacent an end is folded inwardly and superposed on an inner surface of the tubular device adjacent the folded margin.