Abstract: A penetrating washer for use with a carriage bolt. The penetrating washer includes a flat section with a non-circular hole and one or more prongs, ridges, or other protrusions extending from a face of the flat section. A size of the non-circular hole preferably corresponds to a size of a top shaft of the carriage bolt. The non-circular hole can be a polygonal hole with round or sharp corners, for example a square hole with round or sharp corners. Any number of prongs, ridges, or other protrusions can be used, for example four. The non-circular hole preferably is in a center of the flat section. Also, methods of making and using the penetrating carriage bolt washer.