Let be a simple graph with vertex set and edge set , and let . Any edge labeling induces a partial vertex labeling assigning or to , being an element of , depending on whether there are more -edges or -edges incident with , and no label is given to otherwise. For each , let and . An edge-labeling of is said to be edge-friendly if . The edge-balance index set of the graph is defined as . In this paper, we investigate and present results concerning the edge-balance index sets of flux capacitors and -products of stars with cycles.