DB3355 Heavy Duty Clevis Horn System (2)A complete mounting system for large aircraft that can be configured as a pull pull or as two single control horns. Self adjusting design will mount at 90 to center line of the control surface. This system includes premium socket head bolts which provide a non slip head while installing horns. The clevis horns include 4 40 heavy duty swivel ball links for "no slop" precision control. 1 set pkg.