Safety devices for immediately stopping equipment in emergency situations at manufacturing sites with machinery and industrial robot systems. Includes push-button emergency stop switches, pull-cord emergency stop devices, and emergency stop relay units, which are mandatory safety equipment required under occupational safety and health laws. Red push buttons and mushroom-type switches are common, utilizing NC contact structure for reliable stopping operation. In industrial robots and automated lines, installation at accessible positions is required for worker safety and equipment protection. Many products have IP65 or higher dust and water resistance, ensuring reliable operation in harsh manufacturing environments.