There are two basic types of Extended Counter Drives - the Short Extension with an adaptor height of 150 mm and the Long Extension which can be supplied upto a height of 3810 mm.
The Short Extension version is generally recommended for metering applications involving hot, cold or corrosive liquids. It consists of an adaptor casting, having a spindle, which transmits the drive from the bulk meter calibrating mechanism to the counter. A bakelite plate optionally fitted on top of the calibrating mechanism base acts as the thermal barrier.
The Long Extension version is mainly used when operational and space requirements necessitate elevation of counter for better visibility. In this case, the drive to the counter from the bulk meter calibrating mechanism is by a steel coupling shaft, supported at both ends and housed in a steel tube for a smooth low friction transmission. The counter can have a fixed or swivel mounting arrangement. For batching operation, fitment of a preset register is possible, with valve control through an adjustable linkage.