Size M: 4 3/4" outside and 3 1/2" inside. Weight 1 lb 6 oz. Size L: 5" outside and 3 3/4" inside. Weight 1 lb 9 oz. Iron Rings are the original weight training in Chinese Martial Arts. These provide the ultimate in weight resistance. How many can you handle? Sold separately.Size M: 4 3/4" outside and 3 1/2" inside. Weight 1 lb 6 oz. Size L: 5" outside and 3 3/4" inside. Weight 1 lb 9 oz.