The Castle Series Wire Harness with T-PLUG connectors allows you to connect two battery packs in series, combining the voltage of your batteries. For example: two 3S (11.1v) packs will have the output voltage of 6S (22.2v) when connected with this harness. Note: You must always use identically prepared packs with this harness. Both packs must be fully charged and properly bal....

The Castle Parallel Wire Harness with T-PLUG allows you to connect two battery packs in parallel, combining the capacity of your battery packs. For 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 with this harness. Both packs must....