A wheel balancing weight comprising: an attachment clip having a clip portion configured to attach the wheel balancing weight to a vehicle wheel and having a generally flat or planar attachment portion of a trapezoidal shape and no protruding elements with a pair of opposed side edges, the attachment portion being wider along a remote or free edge or end that is spaced from the clip portion and being narrower where it is joined to an edge of the clip portion, thus, the side edges being tapered or angled relative to one another and closer to one another nearer the clip portion and further apart nearer the free end; a mass body having a front side with a like-shaped groove or clip pocket that is cut in the front side, the groove has groove walls spaced apart from one another across the width of the groove and along the sides of the groove, the groove walls mirror the edges of the attachment portion on the clip, the groove walls are also not parallel with one another, but they are tapered and are closer to one another nearer a top side of the mass body and are further apart from one another nearer a bottom side of the mass body, the groove walls are thus angled in plan view, tapering away from one another to match the shape and size of the trapezoid shape of the clip attachment portion, flowed or worked mass body material overlies the edges of the clip attachment portion to secure the attachment portion in the groove, characterized by the edge of the clip portion is wider than the upper end of the attachment portion, creating shoulders on the ends of the edge beyond the side edges of the attachment portion, the shoulders bearing against the top side of the mass body laterally beyond the width of the groove in the assembled wheel balancing weight and therefore prevent the attachment clip from moving parallel to the groove surface but in the opposite direction toward the bottom side, the trapezoid shape keys the attachment portion in the groove and prevents the attachment clip from pulling away from the mass body in a direction parallel to the groove surface and toward the top side. an attachment clip having a clip portion configured to attach the wheel balancing weight to a vehicle wheel and having a generally flat or planar attachment portion of a trapezoidal shape and no protruding elements with a pair of opposed side edges, the attachment portion being wider along a remote or free edge or end that is spaced from the clip portion and being narrower where it is joined to an edge of the clip portion, thus, the side edges being tapered or angled relative to one another and closer to one another nearer the clip portion and further apart nearer the free end; a mass body having a front side with a like-shaped groove or clip pocket that is cut in the front side, the groove has groove walls spaced apart from one another across the width of the groove and along the sides of the groove, the groove walls mirror the edges of the attachment portion on the clip, the groove walls are also not parallel with one another, but they are tapered and are closer to one another nearer a top side of the mass body and are further apart from one another nearer a bottom side of the mass body, the groove walls are thus angled in plan view, tapering away from one another to match the shape and size of the trapezoid shape of the clip attachment portion, flowed or worked mass body material overlies the edges of the clip attachment portion to secure the attachment portion in the groove, characterized by the edge of the clip portion is wider than the upper end of the attachment portion, creating shoulders on the ends of the edge beyond the side edges of the attachment portion, the shoulders bearing against the top side of the mass body laterally beyond the width of the groove in the assembled wheel balancing weight and therefore prevent the attachment clip from moving parallel to the groove surface but in the opposite direction toward the bottom side, the trapezoid shape keys the attachment portion in the groove and prevents the attachment clip from pulling away from the mass body in a direction parallel to the groove surface and toward the top side.