Poly-X (TM) and Poly-EX (TM). is a specially designed polymer material developed by the one of the foremost Chinese Defense Contractor, Ningbo Rongyi Chemical Fiber Science & Technology Co. Ltd. The Chinese Military and their "Elite Forces Group" tasked Ningbo Rongyi Chemical Fiber Science & Technology Co. Ltd. in 2001 to develop a lighter , stronger material that would be capable of stopping the steel jacketed bullets from the Russian Tokarev and the Chinese M-80. Which requires higher ballistic resistance standards than the US NIJ standards for level IIIA. SEG Armor partnered with Ningbo Rongyi Chemical Fiber Science & Technology Co. Ltd. to offer this technically advanced material to our Military and Law enforcement community