Bullet Banana connectors are used to connect ESC and Motors or any other connection.

 Features:

    quality.
    Hook up brushless motor to electronic speed control.
    Low resistance, and gives the best electric flow.
    Female Internal Diameter: About 3.5mm / 0.14"
    Female Connector Length: About 12mm / 0.47"
    Male Internal Diameter: About 4mm / 0.16"
    Male Connector Length: About 12mm / 0.47"