Use to fix D-rings to backing board. Domed head and two legs. In use it is pushed through the two parts to be joined, and the legs spread apart with a screwdriver. It is then inverted onto a hard surface, and flattened with a hammer.
'A' for strut clips and bars, 2.2mm dia.
'B' for most D-rings, 3mm dia.
Brass plated, 3/8" x 11, tub of 1000.