This is a chair conceived to resolve the most diverse, varied requirements. From collective use to domestic use, passing through offices, hostelry, auditoriums or teaching. The seat-back is in varnished beech wood. In the structure, use has been made of painted or chromed steel, with an extensive variety of colours to choose from. The assembly system of LÓGICA allows easy maintenance. The chairs may be joined by means of a connection system fixed to the arms. This is a small piece of nylon, the flexibility of which allows straight or curved rows of seats to be formed for auditoriums, and a piece of aluminium that also serves as a support for a writing flap. This may easily be fitted on either side of the chair for use in classrooms or conference halls. The flap is in synthetic material with an articulation that allows it to be hidden in a vertical position, even when the chairs are fixed together. LÓGICA is a stackable chair in all its versions, thus making storage easy. For this, the frame at the bottom of the chair has been protected with a polyethylene plastic tray, thus preventing scratching from damaging the surface of the seats. The flaps installed do not affect the stacking, and a trolley specifically designed for LOGICA allows the columns of chairs to be transported comfortably.