PNP/NPN inverter modules are not a specific brand but a type of electronic component used in industrial automation. These modules are produced by various manufacturers worldwide, including companies like Siemens (Germany), Omron (Japan), and Allen-Bradley (USA). They serve industries such as manufacturing, robotics, and process control, enabling signal inversion and switching in PLC (Programmable Logic Controller) systems. Key products include solid-state relays, sensors, and interface modules designed for high reliability and compatibility with industrial automation standards.