It was intended to supplement lighter AA guns, ie the 40mm ones, and privide higher altitude cover. Developments in SAM capability however meant that only this prototype was built, though it was used operationally as part of an air defense unit for about a decade.
It weighed in at 25 tons, could hold 52 proximity fused shells and fire 47 of them in 40 seconds. It could also be used against land and naval targets.
An interesting sidetrack development.