These are Wanxin brand lenses.

WX is the lens of Wanxin Optical brand. Wanxin Optics is a glasses manufacturing enterprise with a long history, selling its products in nearly 40 countries and regions including Europe and the United States. Wanxin Optical Group is one of the largest resin lens production bases in Asia and the first enterprise in China's eyewear manufacturing industry to obtain the "China Well-known Trademark".