Abstract: A fastening clamp for connecting a carrier part (13) and an add-on part (14) has a plug-through leg (1), with a plug-through sleeve (5), and a threaded leg (2), which is connected to a thread unit (10). The plug-through sleeve (5) extends away from the threaded leg (2) and has an effective overall height which is greater than the thickness of an add-on part (14). Engagement elements (11) are present on that side of the thread leg (2) which is directed towards the plug-through leg (1). In a pre-assembly arrangement, the legs (1, 2) are spaced apart by a distance which is large enough to allow a carrier part (13) to be positioned between the legs (1, 2) such that it is essentially free of engagement with the engagement elements (11), in which case, once a screw has been screwed into an end position, the engagement elements (11) thus engage with the carrier part (13) such that the fastening clamp is connected in a non-displaceable manner to the carrier part (13).