The very worst made glasses Ive ever owned.  The ear pieces extend a full one half inch beyond my ears (a first) and after wearing them three times, open an inch wider than perpendicular.  As a result, it is impossible to keep them on my face.  Ive never had either problem before.  The ear pieces are also very fragile.  I don't understand how Persol stays in business.  Ive never owned such a poorly engineered device.