This harness will connect two battery packs in parallel. You will effectively combine the capacity (mAh) of the packs. Example: two 3S (11.1V) 6000mAh packs will have the capacity of 12,000mAh when combined with this harness, but remain at a 3S (11.1V) voltage.
Note: You must always use identically prepared packs. Both packs must be fully charged and properly balanced. Both packs must be made by the same manufacturer, have the same C rating, same number of cells (2s,3s,etc.), and both must have the same capacity.