A linearly adjustable device comprising a main body including at least two body sections each having a longitudinal axis, and a linear actuator. The sections are operatively connected together for linear movement relative to one another in the axial direction. The linear actuator is operatively mounted to the main body for causing the relative axial movement between the body section. The linear actuator includes a drive and a power transmission mechanism operatively connected to the drive. The transmission mechanism includes an elongated threaded member operatively connected to one of the body sections and a cooperating threaded member operatively connected to another of the body sections such that relative rotation between the elongated threaded member and the cooperating threaded member causes relative movement of the body sections.
