Lynn Manufacturing Insulating Fire Brick, Heat Insulation Block, Low Thermal Conductivity, 1.25" x 4.5" x 9" Split, Single Pack, 2600-F Rated, for Kilns, Forges, Furnaces, Soldering, 3146P

Great surface to solder silver, casting on top of it and brazing small metal pieces, I was tired of soldering boards not being refractive enough or almost disposable with their surfaces ruined with a bit more than 2200 degrees. For now, it is holding great, just tried for a while.Harder and more porous than soldering boards, thick enough and nice size -might get a second to increase soldering work surface.

Nice softbrick, very carefully packaged. This brick is essentially what you find inside a kiln and not like a hardbrick you would use when casting metal. Love it!

All I wanted was to point a butane torch at some art I was making, and not scorch everything else I own, or burn the house down.This gives me that.Thank you fire brick!

This is a very soft fire brick and is horrible for casting.

Picture speaks for itself. 30 minutes into a forging session and this happens. Going to iron dungeon forge for my next brick. Would not recommend.

Probably a fine product asLong as no welding flux touches it, for instance anything inside the forge like metal scale or flux when forge welding will instantly eat a hole through this

Just what i needed thank you will be paying again very soon

I'm going to replace it into a heater