A choke call includes a bobbin, a pair of windings wound around the bobbin, and two magnetic cores. The bobbin has a rectangular barrel in which a circular hole is defined. The two magnetic cores are partly inserted into the hole of the barrel. The hole is offset from the central axis of the barrel. A central collar extends perpendicular to and at the central portion of the barrel. Two end collars extend beyond and parallel to opposite ends of the barrel. The thickness of the central collar is approximately two times greater than that of the end collars. The magnetic cores collectively form an opening. Within the opening, the gap between the outer periphery of the central collar and the magnetic cores is greater than that between the outer periphery of the end collars and the magnetic cores. A part of the magnetic cores within the hole has a circular or rectangular cross-section.