A pendular unit for an energy harvesting module, PEH, the pendular unit comprising: - a piezoelectric, PZT, transducer beam, the PZT beam extending axially between a proximal end, clamped into a clamping part, and a free distal end that is elastically deformable in bending; and - an inertial mass, that is mounted at the free distal end of the PZT beam and mobile in a transverse direction, the inertial mass comprising two half-masses (64, 64) arranged on either side of the PZT beam at the free distal end of the PZT beam, wherein the pendular unit is adapted to convert a mechanical energy produced by oscillations of the pendular unit under the effect of external stresses undergone by the module into an oscillating electrical signal collected by surface electrodes of the PZT beam, wherein the pendular unit comprises a mechanical connection of the two half-masses (64, 64) to each other on either side of the PZT beam, the mechanical connection being adapted to clamp the PZT beam between the two half-masses (64, 64) to secure the inertial mass to the PZT beam, the assembly being devoid of glue between the half-masses (64, 64) and the PZT beam, characterized in that the mechanical connection of the two half-masses (64, 64) to each other on either side of the PZT beam comprises: at least one added transverse bridging part (66, 68; 78, 78), welded to each of the two half-masses (64, 64), and/or respective complementary and conjugated interlocking shapes (84, 86) of the two half-masses (64, 64), and in that the PZT beam comprises an orifice (70; 82, 82) and/or a notch (72; 88, 88) adapted to be passed through: by the at least one added transverse bridging part (66, 68; 78, 78) or, respectively, by a protrusion of the complementary and conjugated interlocking shapes (84, 86). - a piezoelectric, PZT, transducer beam, the PZT beam extending axially between a proximal end, clamped into a clamping part, and a free distal end that is elastically deformable in bending; and - an inertial mass, that is mounted at the free distal end of the PZT beam and mobile in a transverse direction, the inertial mass comprising two half-masses (64, 64) arranged on either side of the PZT beam at the free distal end of the PZT beam, wherein the pendular unit is adapted to convert a mechanical energy produced by oscillations of the pendular unit under the effect of external stresses undergone by the module into an oscillating electrical signal collected by surface electrodes of the PZT beam, wherein the pendular unit comprises a mechanical connection of the two half-masses (64, 64) to each other on either side of the PZT beam, the mechanical connection being adapted to clamp the PZT beam between the two half-masses (64, 64) to secure the inertial mass to the PZT beam, the assembly being devoid of glue between the half-masses (64, 64) and the PZT beam, characterized in that the mechanical connection of the two half-masses (64, 64) to each other on either side of the PZT beam comprises: at least one added transverse bridging part (66, 68; 78, 78), welded to each of the two half-masses (64, 64), and/or respective complementary and conjugated interlocking shapes (84, 86) of the two half-masses (64, 64), at least one added transverse bridging part (66, 68; 78, 78), welded to each of the two half-masses (64, 64), and/or respective complementary and conjugated interlocking shapes (84, 86) of the two half-masses (64, 64), and in that the PZT beam comprises an orifice (70; 82, 82) and/or a notch (72; 88, 88) adapted to be passed through: by the at least one added transverse bridging part (66, 68; 78, 78) or, respectively, by a protrusion of the complementary and conjugated interlocking shapes (84, 86). by the at least one added transverse bridging part (66, 68; 78, 78) or, respectively, by a protrusion of the complementary and conjugated interlocking shapes (84, 86).