Clockwork selector mechanism

A clockwork column selector mechanism, comprising a mobile including a plurality of columns protruding above a base surface and separated by clearances, said columns and said clearances together forming slots extending along a profile, arranged to, in certain positions of said mobile, enable the insertion of a feeler-spindle or a pin into one said clearance in a transverse direction substantially normal to said profile and substantially parallel to said reference surface, and to, in other positions of said mobile, stop a feeler-spindle or a pin on a transverse surface of one said column, wherein at least one said column includes at least one intermediate transverse stopping surface which is arranged to constitute a stop bearing surface of one said feeler-spindle or one said pin and enable a partial insertion of one said feeler-spindle or one said pin in the thickness of one said slot, and which is located, in one said transverse direction, between the geometric envelopes of two end transverse surfaces which transversely delimit said column.