The Proselect Zinc Plated Rod Couplings are a set of 12 fully threaded rods made of zinc material, measuring 1/2" in length and 1/2" in thread size. These couplings are designed with a zinc plated finish and are manufactured in the United States. The product carries a California Prop 65 Warning due to its materials. Ideal for industrial and business applications, these couplings from Proselect are reliable and durable for various fastening needs.