BLACKHAWK!'s LOK-DOWN sling swivels are precision machined and assembled to exacting tolerances for maximum performance and quiet carry. Made entirely in the USA from premium steel, LOK-DOWN swivels utilize a positive locking mechanism designed to keep the swivel attached to your gun until you remove it. LOK-DOWN Swivel Set. in.¢ Wood screw forend base. in.¢ Wood screw rear base.