9 Electronic devices and instruments for locating metallic and non-metallic objects in the ground, in cavities and under water, namely, ground penetrating radar apparatus, radar detectors, metal detectors, radar receivers with amplifiers, and lasers for measuring purposes; data processing equipment and computers, in particular for use in evaluating data from detection devices for locating metallic and non-metallic materials and cavities; acoustic alarm devices, namely, acoustic sound alarms; non-medical air and gas analysers; electronic indicators, namely, depth indicators; apparatus and instruments for archaeology, namely, ground penetrating radar apparatus, radar detectors, metal detectors, radar receivers with amplifiers, computers, and lasers for measuring purposes; batteries; accumulators; observation instruments, namely, telescopes; stored operating programs for computers, recorded; blank magnetic data carriers; blank optical data carriers; detectors, namely, radar detectors, metal detectors; density meters; electric coils; electromagnetic coils; distance-recording apparatus for measuring and telemeters; telemetric devices, namely, telemeters; wireless telephone apparatus, namely, radio telephony sets; printed circuits for incorporation in electronic devices; holders for electric coils; altimeters; interfaces for computers; calibration measuring apparatus for calibrating ground penetrating radar, radar detectors, metal detectors, radar receivers with amplifiers, lasers for measuring purposes; metal detectors for industrial or military purposes; radar apparatus, in particular ground radar apparatus