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ACOUSTIC LOCATOR BEACONS TO PROVIDE A SOURCE OF UNDERWATER ULTRASONIC SIGNALS; ULTRASONIC SIGNAL DETECTORS FOR USE ON LAND AND/OR UNDERWATER; ULTRASONIC POWER SUPPLIES; ULTRASONIC TRANSDUCERS AND HORNS AND ULTRASONIC TOOLS FOR CONTROLLING AND/OR DIRECTING THE FLOW OF ULTRASONIC ENERGY TO WORK AREAS; [ ULTRASONIC ACCESSORIES IN THE NATURE OF CENTERING RINGS, REACTOR CHAMBERS; ] STRIP FILM PROJECTORS WITH OR WITHOUT SOUND MAGNETIC TAPE RECORDERS AND/OR REPRODUCERS [ OR DISC RECORD REPRODUCERS; ] FILM OR MICROFILM READERS