After working in the high-temperature kiln industry for more than ten years, I have observed one thing: when many purchasing and technical personnel select integrated furnace bricks, the first thing they are most accustomed to asking is - 'What is the content of aluminum oxide (Al₂O₃)?' 68%, 75%, 80%...the higher the number, the more secure it seems. But to be honest, choosing a brick based on its Al₂O₃ content is like buying a car based only on its engine displacement. Large displacement does not necessarily mean stable running, and high content does not necessarily mean durability. Today we will talk about, in addition to the composition report, when choosing integrated furnace bricks in 2026, you should also look at several more critical indicators.