This 30mm key selector switch head, Ronis 455 provides an ergonomic interface for controlling your machine.It is easily installed/replaced on compatible selector switch units and contact blocks via snap-fit assembly.It is clearly distinguishable visually at a distance thanks to its clear color.It is vibration, impact resistant, high pressure washer resistant and dust resistant thanks to its IP69, IP67, IP66 protection, making it ideal for operation in harsh environments.