This Harmony XB4, plain lens green flush head with illuminated ring operates with a spring return / impulse mechanism.This button head with illuminated ring provides an ergonomic interface for controlling your machines.It is easily installed and replaced on compatible complete push button units and contact blocks via snap-fit assembly.It is clearly distinguishable visually at a distance thanks to its illuminated ring and clear color.It is impact resistant, dust resistant, water resistant and vibration resistant thanks to its IP66.It has a metal bezel, this makes it Ideal for applications requiring high impact and vibration resistance.It is designed to fit in a standard 22mm cutout, ensuring compatibility when installing in pre-existing machinery.Its wide range of operating temperatures from -40°C to 70°C allows versatility in usage of product.It provides high brightness for easy identification of function and operation mode, even in brightly lit environments.