Stainless Steel Cotter Pins are used to secure two items together with the use of a common hole. Place the cotter pin in the hole. The bulbous head stops the pin from moving all the way through. Included parts come in 1/16", 3/32", and 1/8" eye diameter variants and run 1/2" to 2" in length. Full assortments of #43689 contain sixteen (16) refills comprised of Hillman item numbers #969 - #971 and #43690 - #43702.