The Medium Duty Fireplace Split Brick is the highest quality medium duty firebrick used for pizza ovens, pottery kilns, fireplaces and temperatures less than 2000F/1200C. The 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. Please note 888 bricks ship per pallet. The brick dimensions are: 9"x 4.5"x 1.25"