The product is a set of 139 vintage Vitro Agate marbles from the United States, ranging in size from 0.59 to 0.64 inches. This collection includes a nice mixture of marbles with one metallic marble still in its original packaging. These machine-made marbles are from the pre-1970 era, making them a valuable addition to any marble collection. Perfect for collectors of vintage marbles, this set appeals to a wide age range from 8 to 16 years and 17 years & up.