Square D EZ Meter-Pak main devices are available as main circuit breakers, main fusible switches, or main lug terminal boxes. EZM main circuit breaker with busway side tap have an integral busway tap allowing for connection to I-Line or I-Line II plug in busway. This main circuit breaker unit supplies three phases in, three phases out with a four wire configuration. This unit has busway taps extending to the right of the main device and allows neutral front installation. It is rated for 208Y/120VAC or 240/120VAC delta and 400A. It comes with a factory installed 3 pole 400A circuit breaker. The compartment has four horizontal 400A rated busbars. The busbars come with Visi-Tite joint nuts for connections, eliminating the need for torque readings. It is compliant with UL standards and the steel enclosure has a rating of NEMA 1.