| 340 / | HD | COMMUNICATIONS: ELECTRICAL |
|
| 384.1 |  | AUDIBLE INDICATION {11} |
| 384.2 | DF | .~> Ultrasonic pest control |
| 384.3 | DF | .~> Simulation |
| 384.4 | DF | .~> Electronic siren (e.g., wail tone or yelp tone warning device) |
| 384.5 | DF | .~> With computer element |
| 384.6 | DF | .~> Piezoelectric |
| 384.7 | DF | .~> Electronic {3} |
| 385.1 | DF | .~> Explosive |
| 387.1 | DF | .~> Weatherproofing |
| 388.1 | DF | .~> Diaphragm (e.g., horn or buzzer) {7} |
| 392.1 | DF | .~> Percussion-type sound producer (e.g., signal chimes or bells) {15} |
| 404.1 | DF | .~> Pneumatic-type sound producer (e.g., whistle or siren) {2} |