The examination of luggage and other containers by x-ray or other technological means may be done at the border with no required showing of particularized suspicion, as long as the means of examination are not personally intrusive, do not significantly harm the objects scrutinized, and do not unduly delay transit. After an x-ray confirmed defendant’s suitcase had a false bottom, and he had given questionable information regarding his travel itinerary, it was permissible for custom officials to cut a small hole in the bag.