Cup cover is made of the food grade PP, the cup cover can be when the cup is used, drinking is more sanitary and convenient; inner ring is made of food silica gel, non-toxic and tasteless resistance high temperature hot and cold. Smooth round cup to give appropriate temperature and texture of the lips. The unique reinforcement of the bottom of the cup, placed more smoothly, the bottom of the cup with a genuine certificate, authentic guaranteed! Safe to buy! The outer layer of the high quality stainless steel, 304 stainless steel liner!