Philip Stein’s greatest achievement was the invention and development of its Natural Frequency Technology, as frequency present in Philip Stein watches helps its wearers sleep better, feel more relaxed and become more focused. Now a byname in luxury watches, Philip Stein was even featured on the Oprah Winfrey Show in 2003. Other iconic features of these watches include a dual time zone facet and watch straps that could be mixed and matched. To date, the company has kept its reputation intact by continuously developing new technologies to make their products even better.