Great general purpose medium duty firebrick used for pottery kilns, fireplaces and temperatures less than 2000F/1200C. Medium Duty Fireplace brick conforms to ASTM Specifications C-27 – Class 4.1.4 and 4.1.5 for Medium Duty and Low Duty respectively and C-1261-98 (which includes C-24 and C-67), as well as, C-16, C-20, C-24, C-38, C-113, C-133. Call for other special shapes large quanties or truckload pricing. size: 9 Inch Straight 64mm (9") straight 230 x 114 x 64mm (9" x 4-1/2" x 2-1/2") 456 brick per pallet. MADE IN THE USA