After a hotplate caused a deadly Brooklyn house fire in 2015, an Israeli designer, Rafi Gabbay, developed a safer version. HotMat, is a new foldable 4-ring hotplate, to give observant Jews a safe, portable and rabbinically sanctioned method of heating up food on the Sabbath. Shipping for Passover.
http://www.timesofisrael.com/hotmat-new-shabbat-hotplate-offers-design-and-safety-appeal/