, 40km, 80km) are designed with high transmit power to compensate for signal loss over distance. For instance, a 40km single-mode module may emit up to +2dBm. However, the receiver's maximum overload threshold is typically much lower, around -3dBm. The transmitted optical power of long-distance optical modules (such as 40km/80km/120km specifications) is generally higher than that of short-haul modules, typically reaching +2dBm to +5dBm. When such a module. The maximum receivable power is called the Overload Optical Power, also called the Saturation Power, which means max optical power detected by the receiving end of the optical module.