Watch strap

a watch comprising at least one case which includes horns, at the level of a first side and of a second side opposite the first side, and a strap formed by a flexible blade with a first end fixed to the case and a second opposite end, provided to cooperate with a device for attaching and adjusting the length of the strap,

• wherein the adjustment device comprises a clasp formed by a cap and a lever between which the flexible blade slides, the clasp being hinged on the case by linking means which define an axis of rotation about which the lever can undergo a rotation in order to be able to move into an open position and into a closed position, the lever comprising an eccentric in the vicinity of the axis of rotation, which is integral with the lever and is provided in order to clamp the flexible blade against the cap and to retain the strap when the lever is in the closed position.