This is the new style Energy Retention Disk / Target 31264 for Clean Burn furnace models CB 1400 CB 1800, CB 2800, CB 90 AA, CB 90 AH, CB 90 BH, CB 90 C and CB 90 D and Clean Burn waste oil boilers CB 200 CTB, CB 350 CTB and CB 500 CTB. This is the latest design from Clean Burn replacing previous Ceramic Targets and Stainless Steel Targets 11385. This target comes with a bolt kit and instructions. It is made from a silica refractory material. It looks similar to an egg carton but much more durable and heat resistant.