A threadlike retainer cord is used to bring a self-drilling and slotting flat nut inserted through a wall into position with the hole in the surface for a screw to mate with the threads in the nut. The nut has an elongated drilling point with serrated teeth along an elongated side. The drilling point makes a hole wide enough for the matting screw and is long enough to go completely through the wall. The serrated teeth on the elongated section are used to make horizontal slots on each side of the hole to accommodate the full width of the nut. The resulting slotted hole is clean and provides a smooth and uniform surface on the inner surface of the wall for the nut to rest against. This fastening system provides a simple way to fasten objects onto walls without having access to both sides. The retainer cord has elongated ends that are larger than the holes they are put through. The nut is put through the slotted hole in the wall and rotates 90 degrees after dropping through the hole. The nut is put into position over the hole by pulling on the cord. In one case the cord goes through a hollow screw while the opposite end is through the threaded hole in the nut. Another possibility is using small holes on both sides of the threaded hole in the nut. The cord is looped through these two holes and aligns the threaded hole in the nut with the hole in the wall when the cord is pulled. This makes it easy to mate a screw with the nut. The flat nut then rests against the inside surface of the wall and has a wide area for holding the object. This provides an improvement in holding capacity for this system.