20 Year AA Medallion Large 1.5" Size vs 1 5/16 Traditional size. Heavy Premium Bronze Sobriety Chip With a large blank area on the back you could engrave on. Note I CANNOT ENGRAVE. Two very detailed lions appear on the back with Courage Wisdom Serenity. This coin is a great high end sobriety gift and alternative to those with the Serenity Prayer on back.