 To remove the earhook, remove the earhook pin by pushing it out with the supplied pin removal tool. Gently push the earhook towards the battery pack to remove. It will click as it detaches. To replace the earhook, attach the earhook to the control unit, ensure the recess of the earhook is aligned with the rib of the control unit, and pull upwards until the earhook clicks into place. Use the earhook pin to lock the earhook in place.