How to charge/balance two TrakPower's

FP sent me a reply today with a photo...it seems that the idea of hooking up the balancers in parallel is much simpler than I though it was. All you need is a simple Y adapter! Very easy. Attached is the photo they sent...those are two 5s packs.

If all it takes is a simple Y, another VB and making darn sure I hook it all up properly, I think I may just go for that as a solution.

I don't quite understand how the charger will know when to stop...does the balancer prevent the charge from coming through once it's cells are fully charged? (I know that's a dumb question, mainly because I've been using an FMA Scorpion charger which charges and balances, I've not even used the one VB I have!)

Thanks guys,

DM