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Shabbos Electric Hot Plate Covers (Blech)

A blech (from the German by way of Yiddish word for tin or sheet metal) is a metal sheet used by many observant Jews to cover stovetop burners (and for some, the knobs/dials too) on Shabbat (the Jewish Sabbath), as part of the precautions taken to avoid violating the halachic prohibition against cooking on the Sabbath.