These buffalo studs are adorable and one of our best sellers! The wood style is approximately .55 inches around and 1/4 inches thick. The acrylic studs are .55 inches around and 1/8 inches thick. The ear wires are sterling silver and nickel-free. Coral pink, mint green, and black matte are made from acrylic materials. The stained wood and natural wood are made from birch. Made in USA