See question above. Can one use the LoMi Cooktop Mat, that is a piece of white cloth material made of silica clot and silicon dioxide. It is heat resistant from 1050°F to 2000°F. They advertise that “All our products are Kosher certified. Also our mats are Passover and blech products.” What is Horav Miller’s Psak?

Horav Shlomo Miller’s Shlit’a opinion is that it can be used for Pesach also. Although it seems that the mat can be kashered by keeping it at a high temperature for the right time, one should not use the same Kosher Cooktop Mat during Pesach and the rest of the year. See the COR Kosher certificate given by Horav Yaakov S. Felder Shlit’a with similar and more detailed instructions.