These are punched out plugs for covering up screw holes when installing Radiation shielding lead Gypsum Board /sheet rock. You get 100 per order. about 6 ounces total weight. Important: There are approximately 100 pieces each. However, they are weight counted and can vary between 95-105 pieces per bag. The discs are 5/16" Diameter and are available in 1/8" thickness