An antenna module incorporates a microstrip patch antenna and a mast antenna in an at least substantially concentric arrangement for communicating signals in multiple communication bands. The fence and knob may be disassembled so that the fence can be positioned on either side of the plate. The attitude of camera in use for tracking is controlled in such a way as to have the tracking object always placed at the center of the display image plane. Thus, the direction expansion evaporator provides a relatively more efficient way for making the frozen product, so as to increase the quality of the frozen product. The first and third portions of the support web surface are arranged opposite each other and the second and fourth portions of the support web surface are arranged opposite each other to define four surface portions of the fabric. A mast sleeve or \u201cluff tube\u201d is arranged or formed adjacent the luff area of the sail, extending from the head to the foot, and sized to accommodate a flexible mast formed of two or more mast sections.