KR104 is a shaft hole adapter designed for knob applications, manufactured by TE Connectivity under the Alcoswitch brand. It features a shaft size of 3.17 mm (0.125 inches) and an overall diameter of 6.35 mm (0.250 inches), providing a compact interface for mechanical coupling. The product is RoHS compliant and ELV compliant, meeting environmental and regulatory requirements for electronic component applications. This adapter is commonly used in control panel assemblies, instrumentation, and consumer electronics where reliable shaft-to-knob connections are required.