These boards have no active circuitry on them. They are for paralleling up the balance taps on Hobby King packs. Each board is 8P and you can choose 4S, 5S, or 6S.
JST-XH-5 (4S – as used in the hard packs)
Remember to account for a balance tap jumper and extension if you are using these to expand the capacity of an HVC/LVC board (see picture). If you use one of these board for an extension your final P will be 6 + 8 – 2 – 1 = 11P. That is 6 slots on the LVC board, 8 slots on the expansion board, then minus two for the expansion jumper and minus one for the balance tap extension. Make sense :-) 11P, so up to a 55Ah pack.