Indoor purpose metal-clad vacuum circuit breaker is fitted with polyvinyl chloride insulated busbar. The metal-clad vacuum circuit breaker is offered in bolted type construction and is provided with sheet metal enclosure in pre-treated and powder coated finish. The metal-clad vacuum circuit breaker is designed in such a way that allows easy access to cable terminals from the rear. Indoor purpose metal-clad vacuum circuit breaker is extendable from both sides of panel.