A percussion device that includes: - an input side; - an output side; - at least one drive transmitter; - a drive transmitter pathway; - a percussion impactor; and - a percussion anvil; where: the drive transmitter pathway is a circumferential pathway around a longitudinal axis of the percussion device; - the drive transmitter pathway includes at least one tooth section including a lift section and a lead section; - the at least one tooth section is essentially one wavelength of a sawtooth wave; - the lift section is inclined away from a base of the drive transmitter pathway; - the lead section is a section of the tooth section which abruptly returns to the base of the drive transmitter pathway; - the input side is rotationally isolated from the percussion impactor; - the percussion anvil is attached to, or forms part of, the output side; - the percussion impactor includes an impact end and a force input end which are longitudinally opposite terminal ends of the percussion impactor; and - the impact end faces the percussion anvil; such that: when in use, and the output section is free to rotate, the at least one drive transmitter and the drive transmitter pathway are configured to act co¬ operatively to transfer the rotational motion of the input side to the output side; and - when in use and limited or no rotation of the output side is possible, the at least one drive transmitter and the drive transmitter pathway are configured to act co-operatively to increase, maintain or decrease the distance between the percussion impactor and the percussion anvil; wherein the at least one drive transmitter and the drive transmitter pathway are configured to act co-operatively to accept rotational motion from the input side and transmit a percussive and/or rotational motion to the output side.