Item No HSP-293504 CNC-machined alu throttle servo horn for use on throttle servos. Alu servo horn offers maximum throttle control by eliminating the flex often associated with composite servo horns. Ultra-strong construction provides very long life and durability. Drilled for 3mm-linkage hardware. The horn has two holes for linkage mounting on both sides, allowing you to quickly and easily change the linkage angle.