An operating lever (23) can be swung to and positioned at three positions, that is, a connected position where terminals (25) are connected respectively to terminals in a power receiving-side connector (30), a provisionally-retained position where the connection of the terminals (25) to the respective terminals in the power receiving-side connector (30) is canceled, and a canceled position where the connection of the terminals (25) to the respective terminals in the power receiving-side connector (30) is canceled, and the retaining of a casing (22) on the power receiving-side connector (30) by lock arms (26) is canceled. A lever stopper (24) positions the operating lever (23) relative to the casing (22), or cancels the positioning of the operating lever (23) relative to the casing (22) by the gripping of the lever stopper in the operation of the lever.