A belt can be sold as a heating conveyor belt for two very different reasons, and the codes stamped or printed on it are the only reliable way to tell which one you have. This guide separates belts running inside ovens and dryers from belts carrying hot material, then works through the marking line by line: cover grade letters, temperature class and short-term peak, carcass and ply codes, the standard the belt claims to meet, and the thickness pair that describes top and bottom cover. It closes with the markings that are genuinely verifiable and the ones that are decoration, plus the questions to ask before a repeat order.