It means Chow Tai Fook brand gold bracelet, and GJJD is the code name of Chow Tai Fook products.

Chow Tai Fook (stock code: 1929) is the largest jewelry company listed in Hong Kong, specializing in Chow Tai Fook brand jewelry, jade and gold ornaments. Is a comprehensive operating enterprise integrating raw material procurement, production design and retail service. With a history of more than 80 years, it is a jewelry brand in Chinese mainland and Hongkong.