QO Load Centers offer premium features like QO breakers, ground arc fault interrupters and surge arresters. QO load centers are designed for residential and industrial use to protect electrical systems, equipment and people. Systems are single or three phase and have indoor and outdoor versions. QO Load Centers enable the use of a full complement of accessories. This yellow service entrance barrier is for QO single phase back fed main breaker applications. This barrier is 2.8 inches tall, 1.75 inches wide and 0.95 inches deep.