Blind fastener (10, 10') for producing a permanent connection between or among workpieces defining a hole when the blind fastener is pulled by a tool to set the fastener by applying a predetermined tensile load thereto, the blind fastener comprising: - a body (12, 12') with a hollow shank (16, 16') comprising a first end (18, 18') and a second end (20, 20') and having a given outer diameter (Ds, Ds'), and a radial enlargement portion forming a body head (22, 22') at the first end (18, 18') of the shank (16, 16'), - a stem (14, 14') with an elongated cylindrical shaft (32, 32') extending along a first axis A-A and a radially enlarged stem head (34, 34'), wherein the shaft (32, 32') partly extends through the hollow shank (16, 16'), comprises a stem-tail (38, 38') which projects from the first end of the shank (16, 16') and a weakened portion, wherein the stem head (34, 34') comprises an underside (36, 36') facing the shaft (32, 32'), wherein the shaft comprises two diametrically opposed depressions (42, 42') provided between the weakened portion and the stem head (34, 34'), characterized in that the depressions (42, 42') extend from the underside of the stem head or in a close vicinity of the underside of the stem head (34, 34'), and is adapted to form an interlock with the body (12, 12') in a mounted position of the blind fastener (10, 10'), wherein the depressions (42, 42'), in a cross-section, have a V-shape with a inclined flat first surface (44, 44'), a second surface (46, 46') comprising a second radius of curvature, the first and second surfaces being connected by an intermediate portion (48, 48') having a first radius of curvature, different from the second radius of curvature. - a body (12, 12') with a hollow shank (16, 16') comprising a first end (18, 18') and a second end (20, 20') and having a given outer diameter (Ds, Ds'), and a radial enlargement portion forming a body head (22, 22') at the first end (18, 18') of the shank (16, 16'), - a stem (14, 14') with an elongated cylindrical shaft (32, 32') extending along a first axis A-A and a radially enlarged stem head (34, 34'), wherein the shaft (32, 32') partly extends through the hollow shank (16, 16'), comprises a stem-tail (38, 38') which projects from the first end of the shank (16, 16') and a weakened portion, wherein the stem head (34, 34') comprises an underside (36, 36') facing the shaft (32, 32'), wherein the shaft comprises two diametrically opposed depressions (42, 42') provided between the weakened portion and the stem head (34, 34'), characterized in that the depressions (42, 42') extend from the underside of the stem head or in a close vicinity of the underside of the stem head (34, 34'), and is adapted to form an interlock with the body (12, 12') in a mounted position of the blind fastener (10, 10'), wherein the depressions (42, 42'), in a cross-section, have a V-shape with a inclined flat first surface (44, 44'), a second surface (46, 46') comprising a second radius of curvature, the first and second surfaces being connected by an intermediate portion (48, 48') having a first radius of curvature, different from the second radius of curvature. wherein the shaft comprises two diametrically opposed depressions (42, 42') provided between the weakened portion and the stem head (34, 34'), characterized in that the depressions (42, 42') extend from the underside of the stem head or in a close vicinity of the underside of the stem head (34, 34'), and is adapted to form an interlock with the body (12, 12') in a mounted position of the blind fastener (10, 10'), wherein the depressions (42, 42'), in a cross-section, have a V-shape with a inclined flat first surface (44, 44'), a second surface (46, 46') comprising a second radius of curvature, the first and second surfaces being connected by an intermediate portion (48, 48') having a first radius of curvature, different from the second radius of curvature.