MKMX-SWC-MS300 IP66 ACCESSORY / MAIN SWITCH FOR FRAME C.The MKMX-SWC-MS300 IP66 Accessory/Main Switch for Frame C provides rugged, dependable power control for difficult applications. Its simple installation and seamless integration assures continuous functioning wherever you need it.MKMX-SWC-MS300 IP66 ACCESSORY / MAIN SWITCH FOR FRAME C The MKMX-SWC-MS300 IP66 Accessory/Main Switch for Frame C provides rugged, dependable power control for difficult applications. Its simple installation and seamless integration assures continuous functioning wherever you need it.