A device and method for targeting objects and specifically for locating intramedullary screw openings is described. The device and method include a target magnet and a sensor comprising an elliptical array of magnetoresistive elements, designed to give information on the three-dimensional orientation of the magnet. The sensor array is designed such that each magnetoresistive element is a member of an opposing pair and relays information on their alignment with the target magnet. The array is connected to a display such that the position of the sensor in relation to the target magnet is easily discerned. The invention is lightweight and portable, capable of operating on batteries and can be used in primitive situations where a stable supply of electricity is not available.