Type-U Six-Arm Serration Servo Horn for Futaba S9152/S9153 - FU1K27101 3pcs (No Screws)  [FU1K27101]

Overview — FU1K27101 Type-U Six-Arm Serration Horn

This serration-style servo horn is intended for use with Futaba S9152 and S9153 servos and is supplied as three pieces without screws. The Type-U six-arm configuration gives several lever positions, and the serrations index onto the servo spline to help prevent slip during load.

Installation is simple for standard spline servos: press the horn onto the spline until the serrations engage, choose the arm that matches the steering throw you want, then secure the horn to the servo output with a suitable screw from your servo kit or parts box. Always check full arc movement before locking the screw down.

When tuning, exploit the six arm positions to alter steering sensitivity and leverage without changing electronic endpoints. Shorter arms reduce travel while increasing mechanical advantage, whereas longer arms do the opposite. The horn is a straightforward mechanical tool for refining steering geometry on RC cars and similar models.