An assortment of ring weld projection studs from The Hillman Group. Ring weld projection studs are screws that form a tight seal to prevent the leakage of water, oil, gas, or other amorphous materials. The ring projection provides a strong, durable weld joint. Included variants come in 5/16"-18 & 3/8"-16 coarse thread sizes and range from 3/8" to 1-1/4" in length. Full assortments of #34628 contain eight (8) refills comprised of Hillman item numbers #34629 - #34636.