A brick having a low thermal conductivity and used as a backing for the more dense refractory brick.
NSN 5925-00-515-2438
NSN 5920-00-144-8031
NSN 6220-01-541-6283
NSN 6685-01-187-2679
NSN 6130-00-138-6042
NSN 5960-01-442-7950
NSN 6650-01-135-2131
NSN 5996-00-910-4462
NSN 5835-00-617-3578
NSN 6620-00-500-0041
NSN 2925-00-802-9387
NSN 6620-01-547-2086