A bobbin includes a bobbin body, two top sidewalls, two bottom sidewalls, four top tabs and four bottom tabs. The bobbin body includes a top surface formed at one end of the bobbin body, a bottom surface formed at an opposite end of the bobbin body and a side surface located between the top surface and the bottom surface. The top sidewalls extend radially outward from the top surface of the bobbin body. The bottom sidewalls extend radially outward from the bottom surface of the bobbin body. The bottom sidewalls are staggered so that there is no overlap area between the top sidewall and the bottom sidewall along an axial direction of the bobbin body. Four top tabs extend away from the top surface at a position where there is no top sidewall. Four bottom tabs extend away from the bottom at a position where there is no bottom sidewall.