A connecting container system for storing various items comprising two or more individually separable, cylindrically-shaped containers each having top and bottom planar surfaces and a clam-shell opening and closing mechanism that is vertically aligned when said containers are vertically stacked. The inventive device is characterized in that it comprises: at least one sensor for measuring a power radiated by an object which is located in the zone, and at least one processing unit for analyzing the power thus measured. The channels are elliptical in shape, and are arranged in alternating directions around the face of the insert. The electrical signal can have an increasing slope when the duct door is actuated into an open position. The heaters have at least two electrically conducting paths of which the resistances of the electrically conducting baths are substantially equal such that in use uniform heat distribution is achieved.