Robuta

https://www.ktceramicfiber.com/product-page/insulating-fire-brick-2800f-2-5-x-4-5-x-9 Insulating Fire Brick 2800F 2.5"x4.5"x9" | KT Refractories Insulating fire bricks (IFBs), also called soft bricks, are light weight. They can be easily cut by hand tools. Insulating firebricks have high porous rate and... insulating fire brickktrefractories