You may mount one or two Sony wireless receivers on the bracket using the S Clip (Pictures here show two Sennheizer receivers but one or two Sony receivers are mounted in the same fashion).
Place the S Clip on the back side of the Bracket with the tab angled downward as shown in the 2nd and 3rd picture. Insert the screws through the holes in the S Clip and into the threaded holes in the bracket. Slide the receiver over the top of the bracket until the spring clip locks over the tab on the S Clip.
The most convenient way to mount a second receiver is to add the Cold Shoe-1 to the bracket and slide the 2nd receiver into the shoe using the cold shoe mount that come with the receiver.