This Harmony XB4 emergency stop / shutdown 40mm mushroom head modular red push button operates with a latched key release (key no.455) mechanism. It has a metal bezel. This emergency stop / shutdown button, also called EMS (Emergency Machine Stop) and EMO (Emergency Off), is easily installed into a standard 22mm diameter cut-outs and connected with simple screw-clamp connections. It is clearly distinguishable visually at a distance thanks to a clear color and a prominent 40mm mushroom shape. It is impact resistant, dust resistant, water resistant and vibration resistant thanks to its IP66, making it ideal for operation in harsh environments.