1.-Height adjustment: This must be adjusted in relation to the floor to the seat in such a way that the feet are well supported on the ground, in a 90-degree position between the hip, knee and ankle, which will allow for optimum alignment with the trunk or spine (maintain always the soles of the feet resting on the floor).
2.-Seat depth adjustment: this feature allows you to adjust the depth of the seat relative to the backrest to maintain even support for the femur. The depth must be adjusted in relation to the length of the extremities according to the physical complexion of each user.
3.- lumbar adjustment: A backrest with lumbar support allows to provide adequate support in the lumbar curvature (lower back). The lumbar support can be part of the integral design of the backrest represented with a support curvature, or an independent bearing on the backrest that allows the height to be adjusted according to the physical complexion of the user (always maintain the correct height to provide better support to the lower back).
4.-Adjustable headrest and cervical support: Some chairs have an adjustable headrest accessory which allows the user to maintain support in the cervical part and in turn in the head when reclining (adjust the angle and the appropriate height for optimal support).
5.-Adjustable arms: Some chairs have this accessory with adjustable arms that allow you to work in a pleasant position, adjusting them to an optimal work posture.