The VLTOR CASV Picatinny kits from VLTOR are direct replacement rails used on the CASV series of handguards. These rails are machined from aluminum stock and are of Mil-Spec specifications. All hardware needed for installation is included. Made in the USA Kit includes: (1) Five inch rail section (2.16")(2) Four inch rail sections (3.75")(2) Two inch rail sections (5.31") FeaturesMil-Standard 1913 rails5-piece kitMil-Spec type III hard coat anodizedPre-drilled for mounting