Muffle furnace specifications generally include maximum and continuous operating temperatures (e.g., 1100°C, 1200°C, or 1800°C), inner chamber dimensions (volume, height, width, depth), the type of heating elements (e.g., Molybdenum disilicide, Kanthal, Nichrome), the type of thermocouple (e.g., Type B, Type K, Type R), the insulation material (e.g., ceramic fiber, Zirconia fiber), power requirements (voltage, phase, wattage), the furnace door type, the temperature controller (e.g., LCD touch screen, PID controller), and safety features such as over-temperature protection and alarms.