This Harmony 9001K Black Keyed E-Cam Selector Switch has 2 positions and operates with a holding mechanism. The key can be removed in the left and right positions. It fits into a 30mm hole. This key operated selector switch provides a versatile interface for controlling your machinery. It installs easily into a standard 30mm diameter panel cutout and provides authorized personnel with a safe way to switch between process and machine operating modes. Its IP66 rating makes it shockproof, dustproof, waterproof and vibration resistant, making it ideal for use in harsh environments.