This is the connector for charging Hitec Trancmitter batteries.
It will work with Packs for Optic 6, Eclipse, Laser and the new Aurora 9.
Note:
This connector comes with pigtail wires only. You will need to splice it into your Octopus charging harness or install Deans Female connector and use it with your existing Deans charging harness, or solder on 4mm Male bullet connectors on the end of the pigtail and plug in directly to the charger, or just install a connector of your choice.