The invention relates to a bio-medical electrode (100). In a preferred embodiment, an electrode interface comprises a top part (10) with an aperture and a bottom part (20). The bottom part (20) has a head portion designed for a fixation in said aperture and a flexible flange that clamps electrode sheets (31,32) in the connected state of the electrode interface such that the contact force between top and bottom parts is approximately constant during lifetime of the electrode interface. The top part (10) may preferably have the shape of a disk of magnetic or magnetizable material. The bottom part (20) may preferably be made from a conductive plastic such as ABS. The electrode interface may particularly be used in a TENS device.
