filter cartridge and canister 1. ues quality material 2. light and handy 3.enviroment-friendly 4.timely delivery,low price Sheng Ann Company was founded in 2005, the total investment of more than 5.8 million yuan, covers an area of 20,000 square meters, more than 200 employees, with modern production equipment and capabilities strong Laboratory, is a production of dust masks, gas mask and helmet ...