<p>A striker (11) is raisably and rotatably supported by and connected to a seat body (1) and is usually held in a rotated position where the striker (11) is lowered to a position along the shape of the seat body (1). When the seat body (1) is moved and stowed, the striker (11) is raised to and held at a rotated and raised position where the striker (11) can be engaged and locked to a lock device (20). Elasticity of an opening spring (15) and rubber body (17), which are arranged between the striker (11) and a connection section (12), enables the striker (11) to be forcibly moved in the normal and reverse directions from a state in which it is held at the rotated and raised position.</p>
