An insulative module body for a bus system has at least two first channels, each adapted for at least partly receiving a bus bar. Each first channel extends through the body along one side thereof, and is open to the outside at one side and at both longitudinal ends thereof The body has at least two second channels, each adapted for receiving a power connection element for cooperating with a complementary circuit breaker contacting element. Each second channel extends generally transverse to the first channels and is open at one longitudinal end thereof The first and second channels respectively extend through the body in a first plane and a second plane generally parallel to the first plane and offset therefrom. The first and second channels cross each other in respective parallel, offset planes. The body includes at least one opening for each second channel to connect with one first channel.