10 comprises a mandrel 20 cooperatively received in an anchor member 30 and may also include a spanner wrench 40 for engaging the anchor member 30 fig1 a also illustrates the relative position of the steel stud 70 and existing wall 80 in relation to the thin wall fastener assembly 10 fig1 b illustrates the preferred relative position of the corrugated steel stud 75 and overlaid concrete floor 90 in relation to the thin wall fastener assembly 10 referring to fig2 the mandrel 20 preferably comprises a bolt like structure capable of setting the anchor member 30 by rotational force in order to provide sufficient rotational force to set the anchor member 30 the mandrel 20 preferably comprises a shear resistant material such as steel although a variety of materials acceptable for such use are well known as shown in fig2 and 3 the mandrel 20 preferably includes a hexagonal head 22 at one end and a shaft 24 extending from the hexagonal head 22 the hexagonal head 22 is preferably sized to accommodate any standard or metric sized wrench in alternative embodiments the head may be any practical shape that can be rotated by a tool such as a wrench screwdriver or the like preferably the distal end of the shaft 26 includes an externally threaded.