Features:

It can protect the charging batteries when short circuit happens.
It can support combined use for three parallel charging boards ( It means you can charge eighteen batteries which have the same characters at the same time).
It has 20Z-thick copper foil, so it can withstand continual current of 30A.
It can prevent each cell overcharge, so it can improve the balance efficiency. And the later period of the balance charging cycle is shorted substantially.
It consumes ony 1/6 of the time when charging six batteries separately consumes, so it can save the total charging time.
It avoids the trouble of replacing batteries repeatedly.