MCB (Miniature Circuit Breaker) is a distribution box that is fixed or provided in every apartments in modern societies. Instead of MCB box, a 32 Ampere DP switch was fixed that had an on-off switch. MCB box concept didn't exist as they were not aware of such a thing as MCB.
In every society there’s a Meter Room. This meter room has boxes/ switches that supplies electricity to every apartment in the building individually. The current passes through wires and cables from the meter room to the MCB box that is fixed in every apartment. The wires/ cables that run from meter room to each apartment is always concealed wiring. The electric connection/distribution for each rooms in an apartment is done from the MCB.