Commonly used in wood/corrugate knockdown furniture applications, these wood inserts from Hillman are built to receive a machine screw or connecting bolt in order to fasten pieces together. Most commonly, these types of inserts are either hammered or screwed into place depending on the fastener type. Included inserts run 3/8" to 13/16" in length and come in 6-32, 8-32, 10-24, 1/4"-20, and 5/16"-18 thread sizes. Full assortments of #57236 contain seven (7) refills comprised of Hillman item #'s 412274-412280.