QON OEM mounting bases are for the mounting of plug on QO, QO GFI, QO AFI and QO EPD circuit breakers. These OEM mounting bases are available in single and three phase versions. This QON OEM mounting base is for main lugs of 40 A at 120/240 VAC single phase. This unit provides 10 kA breaking capacity based on the circuit breakers installed. This mounting base has 2 spaces for 1 pole breakers. A neutral assembly is supplied with this OEM mounting base. The main breaker will accept 14 AWG to 6 AWG copper and 12 AWG to 6 AWG aluminum wire. The QON mounting base is UL component recognized.