From the Manufactor
This Pigtail Connector is used primarily to connect speakers to the WOW Motherboards
Some of the other available Motherboards have 2-Pin JST Connectors for connecting the speaker and if you choose to use a speaker other than the one that comes with your locomotive you will need one of these connectors to plug it in
Attached to the 2-Pin JST Connector are (2) 30 Guage Violet wires for hard wiring to your speaker (or other application)