Insulation bricks are commonly used in electric and gas kilns where there is minimal abrasion against the lining of the kiln. This is due to the bricks being lightweight and not very dense. 23Grade bricks can withstand a maximum service temperature of 2300 degrees Fahrenheit, 26GD, 2600 degrees and 28GD, 2800 degrees. They can either see the hot face of the kiln or be used behind another layer as insulation. We can also supply these bricks cut to specific drawings. Cutting options are available on our website under the heading "cutting options". However please enquire at email@example.com if you have a special shape you wish for us to quote. Typical analysis sheets are available upon request for these high temperature resistant bricks.