Elevator Bolts have a square neck that resists turning when a nut is tightened or removed. The large, flat head provides a greater bearing surface for soft materials. Variants included in this assortment feature a coarse 5/16"-18 thread size. Full assortments of #46255 contain nine (9) refills comprised of Hillman item numbers #4753 - #4755, #398505, #398508, and #398509. Full assortments of #46255 contain two (2) refill boxes of items #4753 - #4755.