Millboard sheets are non-asbestos and non-ceramic fiber. They are for high temperature applications in centrifugal casting. These fiber boards possess high temperature capability, in excess of 1,000°C, and low thermal conductivity (K value), less than 0.1 W/mK, making them the first choice for thermal insulation applications.

Millboard is commonly used as an insulating barrier between endplates and the metal being poured so endplates do not have to be coated with mold coating with each cycle. Millboard usage has been successful in preventing metal from sticking to the endplates, resulting in lost production time or scrap endplates or castings.