A clutch is configured, when a driving-side rotor is in a non-driven-rotated state, to prevent rotation of a driven-side rotor by setting a rolling element in a lock state in which the rolling element is held by a control surface and a collar. The clutch is configured so that when the driving-side rotor is driven and rotated in the lock state, the driving-side rotor pushes the rolling element via two circumferential holders in a rotation direction to release the rolling element from the lock state. Each of the two circumferential holders includes a guide portion configured to guide the rolling element toward a radially inner side of the collar when the rolling element is released from the lock state.