Abstract: A positive-locking cluster mount for supporting electrical transformers and like heavy objects from upright poles characterized by bearing plates held in circumferentially spaced relationship about the pole by adjustable link members and end links each having singular hook ends that engage into the slotted side walls of the bearing plates and are locked into initial loose, though positively connected, positions by the placement of the diverging support brackets thereon. This facilitates the placement of the partially assembled cluster mount at a desired position on the pole and also facilitates the final connection and tightening of the cluster mount thereabout to receive the transformers. The support brackets are assembled in outwardly diverging paired relationship from bearing plates of different lengths to accommodate small and large transformers.