An adapter for mounting a mounting structure on a flush mount receptacle base. The adapter includes a mounting base and an anchor. The mounting base includes a rotatable drive member with an interface surface configured and arranged for placement on a mounting surface, the rotatable member also has a bore extending thereinto and aligned with the interface surface, and the bore is at least partially threaded.The anchor extends into the bore of the drive member, the anchor has a shaft with first and second end portions and defining a center axis, the first end portion of the shaft is threaded to mate with the threaded bore of the drive member and configured and arranged to rotate relative to the drive member, the anchor also has at least one hook coupled to the second end portion of the shaft and laterally offset from the center axis of the shaft.