Pair of vintage C.P.A.M office armchairs 1960s

Very nice vintage office armchairs They consist of a metal base with castors in a very original shape and a seat in orange fabric. The chairs are adjustable in height at backrest level (it is possible to prefer a support at lumbar or backrest level) and in height by means of a knob at the metal foot. These armchairs belonged to the C.P.A.M. de l'Ain and they are numbered (one of the armchairs has a label with the inventory n screwed under the seat). Excellent general condition, visible on the pictures 1960s