Upper and lower handguard sections interlock providing the rigidity and stability you need in addition to solidly mounting to the delta ring and handguard end cap - Bottom rail can mount to front sling mount for additional rigidity if forward sling swivel is removed. - Two quick detachable sling swivel mounting points - First lightweight polymer handguard designed for use with gas piston systems. - Manufactured from a special high temperature resistant polymer - Includes heat shields - Includes 4 interchangeable rails - Two interchangeable bottom rails 4