https://www.gobilda.com/3-5mm-bullet-connector-pack-mh-fc-x-5-fh-mc-x-5/

This connector pack comes with five 3.5mm (MH-FC) bullet connectors and five 3.5mm (FH-MC) connectors.  These are the same connectors as found on the Yellow Jacket Planetary Gear Motors.  They provide a reliable connection in a compact form-factor for wires up to 16AWG.