of our inflatable rentals have a Watchdog system included. This device alarms at any sign of leak and/or deflation in the inflatable system, alerting bouncers to exit the inflatable until the pressure is restored and is safe for use. The ASTM (American Society of Testing & Materials) requires these sirens for any inflatable over 8ft tall, due to the tip-over risk associated with the unexpected deflation of an inflatable unit.