Godox 1 To 2 Y Adaptor DB-01 Up To 4 Speedlites

The DB-01 one into two splitter cords, which allow 2 flashes to be connected to each battery port.

So up to 4 flashes connected to each battery pack. (When 2 of these cables are purchased.)

Using these cables will have some effect on recycle time, but the PB960 could easily handle 4 speedlights. It is quite similar in capacity and speed to using four separate 8 AA cell packs.