The invention concerns a metal fin for heat exchanger with tubes, comprising means for increasing heat transfers consisting of diverting conformations (10,11) each arranged upstream and downstream of an aperture (3) when considering the direction (F) of air flow, to force the air to pass either side of said aperture, the upstream (10) and downstream (11) diverting conformations of two superimposed apertures (3) belonging to one same column extending along a determined length so that they substantially rejoin at the plane of extension (P) of offset apertures. (Figure to be published: FIG. 2).