Abstract: A generally rigid, plastic housing has therein a pair of chambers, one of which is larger than the other, and each of which opens at one end thereof on the front of the housing and is closed at its opposite end by an integral back wall of the housing which is secured by a pair of plastic bolts to the plane surface of a rather rigid, laminated bus bar. Secured in each of a pair of spaced socket recesses in the housing back wall is a female socket terminal, one of which extends into its associated recess from a conductor in the bus bar, and the other of which is connected to another, male terminal which is housed in the other chamber. Each of the two socket recesses opens on the larger chamber, and the sockets therein are disposed to accommodate a pair of male terminals which project from a circuit breaker releasably housed in the larger chamber. Also, an additional male terminal projects from another conductor from the bus bar into the other chamber adjacent the other terminal located therein.