A connector 1 has a housing 4 including a side wall 42 extending from a base plate 41, a pair of projections 45 projecting from the side wall, and a lever 5 including a pair of plate members 50A having a guide groove 53 and a plate connecting member 50B connecting the pair of plate members. The lever is positioned from a release position to a slide start position, at which the surface of the base plate is in parallel to and slid along the lengthwise direction of the guide groove 53, and tube members 59, 71 and locking members 46, 58 are engaged. A first surface 5a at a side apart from the guide groove is perpendicular to a slide direction at the slide position and a second surface 5b at a side near to the guide groove is perpendicular to a connecting direction Z at the release position. When the lever 5 reaches a lock position, detect connectors in tube members 59, 71 become engaged to close the power circuit.