I-Line™ Busway offers a complete line of compatible, sandwich-type feeder and plug-in busway lengths, fittings, and plug-in units. I-Line plug-in busway has options up to 1600A for circuit breaker plug-ins and 1200A for fusible plug-ins. Circuit breaker and fusible plug in units are available in 3 phase, 3 wire or 3 phase, 4 wire configurations, with Aluminum or Copper conductors, for system voltages up to 600 volts. This unit will accept up to a 70A QO circuit breakers. This plug-in unit is 3 phase, 4 wire with integral ground bus systems. This plug-in unit is a QO circuit breaker enclosure with 3 spaces and 70A max. I-Line Busway plug-in units are UL listed and CSA certified.