This vintage Akro Agate corkscrew marble is a great addition to any collection. Measuring at .61 inches and in mint condition, this machine-made unit has a unique design with corkscrew patterns. Made in the United States pre-1970, this marble is a true classic and a must-have for any marble enthusiast. The brand is Akro Agate and it is sold as a single unit. This item has not been modified in any way.