This items was soldered with 3.5mm Female banana connectors, effectively avoid welding problems; Product Features 1. Safe power-on function: When the power is turned on, the motor will not start immediately no matter what position the throttle stick is in, to avoid personal injury 2. Throttle stroke calibration function: adapted to different remote control oils The difference in door stroke improves the linearity of the throttle response, providing a smooth and delicate speed control feel and first-class speed control linearity Program setting items: Battery type: Li- (lithium battery) / Ni- (nickel cadmium or nickel metal hydride), the default value is Li- (lithium battery). Due to different batches, there may be differences in product appearance, color, and printed text, which will not affect the use. color: Black Material: metal+plastic Package Contents: 4 x ESC Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.