This Harmony XB5 emergency stop / shutdown 60mm mushroom button red button head operates with a locked twist to release mechanism. It has a protective collar. This emergency stop / shutdown button head, also called EMS (Emergency Machine Stop) and EMO (Emergency Off), provides an ergonomic surface for controlling your machines. It mounts easily onto compatible complete emergency stop and shutdown buttons. A clear color and distinctive 60mm mushroom shape make it easy to see from a distance. Thanks to its IP66 protection rating, it is shockproof, dustproof, waterproof and vibration resistant, making it ideal for use in harsh environments.