An assortment of heat-treated automotive studs from The Hillman Group. Automotive studs are a headless bolt that is threaded at both ends with the center portion remaining unthreaded. They are used to insert one end into the head or block and then insert a nut or washer on the other end for applications such as bolting the exhaust manifold to the head. Variants included in this assortment feature a 1/2" diameter and range from 1-3/4" to 3" in length. Full assortments of #45980 contain five (5) refills comprised of Hillman item numbers #408069 - #408073.