Guanqin Women Automatic Mechanical Self-winding 100m Waterproof Calendar Ceramic 36.5mm Watch (White) Automatic Mechanical Movement, accurate, lasting and with long service life. Selection of high hardness sapphire crystal, whose hardness is only to diamond, don't afraid of dill and smash, with the quality high temperature resistance and super anti-corrosion Water-resistant to 100m Additional functions: Calendar Case and bracelet are made of ceramic