What is "hubometer"

alt. A device mounted on the axle of a vehicle's wheel to measure the distance travelled. n. A device mounted on the axle of a vehicle's wheel to measure the distance travelled.

A hubometer (hub, center of a wheel + -ometer, measure of), or hubodometer or simply hubo, is a device mounted on the axle of an automobile or other land vehicle that measures distance traveled.

The whole device rotates with the wheel except for an eccentrically mounted weight on an internal shaft. This remains pointing downwards and drives the counting mechanism as the body of the hubometer rotates round it.