Trijicon ACOG Internal Adjuster Caps And Lanyard This caps and lanyard set for the ACOG is designed to fit those ACOG's that have an -Inch internal -Inch adjuster Adjuster has a low profile and sits inside a brass setting Adjusted with the use of a tool For help in identifying adjuster types, please contact our Customer Service Department at 1-800-338-0563 or visit the Contact Us page