M-frame Square D molded case circuit breakers are rated up to 800A and 600VAC and interrupt excessive current flows to protect devices from electrical damage. They're used in construction, commercial buildings, oil and gas, and other industrial and commercial applications. Their current-carrying parts, mechanisms, and trip devices are contained in a molded case. Depending on your application, Square D’s “M” frame might be the right frame for you. It has an amperage rating of 300-1000 amps, which makes it the ideal choice for larger industrial loads. Depending on your needs, the “M” frame has different voltage options that range from 240 vac up to 600 vac. It also has either a 2 or 3 pole configuration. The “M” frame comes in two different designs: lug-to-lug and I-line. A traditional lug-to-lug frame has lugs on both ends while the conventional, I-line, bus-mounted frame has lugs on one end and a crown on the other, which makes installation a breeze. Agency advantages supply the following brands: ①Allen-Bradley( Rockwell Automation)Series ②Square D（Schneider Electric） Series ③Eaton - Cutler Hammer (Westinghouse )Series ④SIEMENS PLC Series，Siemens CNC system ⑤Eaton moller Series