The clock and bells originally formed a central feature of the old Carterton Post Office on the same site. The post office tower was raised in 1903 and the mechanisms were installed four years later.
Little is known of the clock during its years of operation in the post office, where it remained until a 7.2 magnitude earthquake struck the region on June 24, 1942, that severely damaged the tower.
The clock and bells remained stored for the next two decades until rediscovered by council officers who realised their worth to the town.
The reinforced concrete clock tower, which was built in 1962, stands 14m tall and features three floors or chambers that straddle four leg-like support structures.
The first floor houses the clock workings, which drive a 200kg pendulum swinging on an arm 2m in length. The pendulum, which is swung by electric winch-raised weights, in turn operate by cable the five bells and hammers on the second floor.
The third floor comprises a quadrant operated through a shaft extending from the first floor mechanism that in turn drives the hands on each of the four clock dials.
Apart from the clock faces, hands and automatic electric winding motors, the clock mechanism remains as it was originally constructed.