The CCITT, considering that pulse code modulation (PCM) multiplex equipments are already used in various countries, in particular to provide a large number of short-distance telephone circuits on certain pairs in existing cables, and in order to minimize the number of different PCM multiplex equipments providing circuits which may be used in international connections, recommends that Administrations concerned should make their choice between the two primary PCM multiplex equipments described in Recommendations G.732 and G.733.