Abstract: A precast insulating material member for insulating a furnace skid rail includes a precast insulating material portion containing a crisscross reinforcing structure. The crisscross reinforcing structure is comprised of a pair of arcuate-shaped rods which are welded together intermediate their ends, each rod having end-eye portions which extend outwardly from the corners of the U-shaped precast insulating member. Positioned about the crisscross-shaped rods are coil members which assist in reinforcing the insulating portion of the member when the reinforcing structure is embedded within the insulating portion. The end-eye portions of the rods provide a mechanical lock of the insulating member to a skid rail pipe when the eye portions are moved into engagement with the outer surface of the skid rail pipe.