Siemens MBK Series circuit breakers are designed to facilitate both low and high interrupting capacity requirements for the protection of industrial equipment. These devices feature a thermal-magnetic trip unit providing long-time and instantaneous current limiting functions against overloads or short-circuit conditions and a plug-in design which comfortably mounts into all kinds of panelboards and switchboards. Choose from a wide range of these bolt-on circuit breakers available in 100 and 225A current ratings on Raptor Supplies.