Shabbos Proof - Automatically Self-Adjust Zman Switch Shabbos Timer Shabbos settings built in - Freezes light switch on Shabbos / Yom Tov Can be Set by Time or Sunset - Automatically adjusts for changes in sunrise, sunset, and DST Programmed Until 2050 Automatically adjusts for Shabbos / Yom Tov (even two days) Approved by leading Rabbonim - Adjusts for 72 min. Rabbeinu Tam