Many thousands of bulk-oil circuit breakers manufactured by Brush Switchgear since 1963 formed an integral part of the VSI (single busbar) and VTD (double busbar) range of switchgear. Many of these circuit breakers are approaching or have exceeded twenty five years operational service life. Within the MV switchgear sector, there is now increasing interest in the options for the economic replacement of ageing oil based switchgear with switchgear that utilises non-flammable substances (vacuum or SF6) as the insulating and breaking medium. One such option is to retain the fixed portion of the switchgear and replace the oil circuit breaker with a modern technology circuit breaker. We can supply a type tested vacuum circuit breaker as a direct retrofit for the oil circuit breakers in the VSI and VTD switchgear or to provide a means of equipping a skeleton panel. This vacuum circuit breaker has more than two decades of reliable and proven operational service experience throughout the world in the FKI Switchgear VMV range. Only very minor modifications are required to the existing switchgear fixed portion.