Sinox Metal Co., Ltd, located in very convenience place of Guangdong province, is one of the earliest professional manufactures in researching and producing spring boxes for rolling shutter since 2003. The products have been exported to Europe, America etc market for many years.  To pursue market opportunity actively and meet customers' demands in great extent, our company keeps improving the products with more specifications and varieties. The marketing coverage is steadily expanding.  Enjoying good reputation from all the customers worldwide, we are the reliable partner you can trust in China.