ZEDEL

An adjustment system comprises a strap and an adjustment buckle configured to adjust the strap. The adjustment buckle comprises a body defining a first through hole and a second through hole extending over the thickness of the body. A partitioning wall is fixed to the body. The partitioning wall separates the first through hole and the second through hole in a first direction perpendicular to the thickness of the body. The strap makes a loop inside the body and passes round the partitioning wall. A cover is fixed to the body and installed facing the partitioning wall. The cover and the partitioning wall are separated by a larger distance than the thickness of the strap.

A headband comprises a strip forming a part of a ring around a user's head. An adjustment device adjusts a circumference of the ring by moving one end of the strip that is fixed to an attachment point movable with respect to the body. A rotary actuator is functionally connected to the adjustment device by means of a transmission so that rotation of the rotary actuator results in movement of the attachment point. The adjustment device comprises a threaded section and a nut. The nut and threaded section form a helical link, wherein rotation of the rotary actuator results in movement of the nut along the threaded section. The nut or threaded section moves along a longitudinal axis of the threaded section and supports the attachment point. A helmet comprises such headband.