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Desk chair

Various types of chairs, particularly desk chairs, chairs to be used with work tables, drafting tables, and the like, have a combination seat-and-back tilting mechanism which permits ilting back of the seat and of the back of the chair up to a predetermined fixed position; or to lock the chair in a desired predetermined e.g. tilted position. Providing the employee with a desk and desk chair which is comfortable and provides good ergonomics throughout the many long hours is increasingly understood to be a critical factor in maintaining the attention span. Desk chair mats for office and home use has a main portion on which the desk chair rolls, and can include a forward lip portion which is adapted to extend partially into a desk well, and on which the feet of the person sitting in the chair can rest. A desk chair mat is typically formed of a semi-rigid plastic, and has an array of short, sharp spikes on an underside thereof, which hold the mat firmly in place on the carpeting. Synchronized desk chairs usually have a spring, such as a locking-type spring element. The spring may be a mechanical spring, or may be a gas spring, a hydraulic arrangement, similar to a dash-pot, or the like.

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