Abstract: A flat retainer device has elongated fingers on the left and right sides thereof, said fingers running opposite a side wall of the central portion of the retainer. A slot is formed between each of the fingers and the central portion, the fingers and the main body portion forming a locking hook structure. A protuberance is formed on the lower portion of each side of the central portions opposite each finger, these protuberances closing off most of the opening to the slot on the free end of the fingers. The left and right hand sides of the device are mirror images of each other and have the same structural characteristics. The top and bottom ends of the central portion of the device have indentations formed therein. An elongated groove is formed in the slat, the length of this groove being designed to receive the central portion of the retainer member with the indentations thereof abutting against the end walls of the groove in a force fit relationship.