Uses a weight attached to a laser marked cable or tape, and is principally designed for use during the installation of monitoring wells. The Tag Line also provides a simple method to measure the depth to the bottom of a well. The cable or tape is mounted on a sturdy free-standing reel with a carrying handle, weight holder and brake. It comes in standard lengths of 100 ft. to 1000 ft. (30 m to 300 m). Other lengths are available by request.