Abstract: An automatic revolution counting and data transmission device for measuring full or partial revolutions of a shaft, processing, storing, and transmitting said revolutions and related data. An embodiment of the invention as a hubodometer for measuring rotations of a wheel uses of a housing (1), printed circuit board (3) with all electronic circuitry for counting data, data storage, and two way data communication, and an anti-rotation device. A low power radio frequency transmitter and receiver are used to receive commands and to transfer stored data to a receiving unit which may be a portable battery-powered unit or a fixed-mount unit. Such data transfer by RF link eliminates the inherent problems associated with visual readout or optical data transfer from units located where dirt grime buildup is common.