An assortment of button-head socket cap screws from Hillman. Socket cap screws carry a recessed internal socket drive to add strength. They are commonly used on machine parts, manufacturing equipment, and other mechanical applications. Variants in this assortment range from 3/8"-16 to 5/8"-11 in coarse thread size. Full assortments of #43568 contain ten (10) refills comprised of Hillman item numbers #3888 and #43569 - #43577.