This is the Spektrum Dual I/O 3 Wire Switch Harness.Features:
- Two separate battery inputs
- One charge jack
- Two separate receiver plugs
If you're interested in using dual batteries with two separate receiver inputs, then this switch is what you’ve been looking for. Just plug in two batteries with standard connectors and plug the receiver plugs into two separate ports on the receiver. There is one charge jack that charges both batteries.