Shenzhen Great Wall Development Technology Limited is a large-scale high-tech export listing company focusing on R & D and production of hard disk head products, multifunctional electric meter products and tax-controlled cash register . The company has branches in Hong Kong, Singapore and the United States and R & D teams by integrating R & D, production and sales into one. The company took the lead in passing ISO9001 and other quality system certifications in China and introduced and promoted advanced management methods such as 6Sigma and IE (industrial engineering) technologies. Its flagship product, Hard Disk Head, is the second largest manufacturer of magnetic heads in the world, accounting for more than 10% of the global market share. Electric meter products are distributed in Europe, South Asia and Southeast Asia, with cumulative exports of more than 16 million units, set three "Shenzhen Enterprise Records" and become China's largest manufacturer of remote control meters and systems R & D. The company is the largest R & D and production base for receipt issuers in China, with its annual production capacity reaching 700,000 units as the the first batch of tax-controlled cash register manufacturers and production licenses.