This SB20 Sonic Location Beacon™ is an audible beeping device that may be used to help locate model rockets, model airplanes, payload carrying balloons, and so on. This device creates repeating 3600 Hertz patterned beep tones at a volume of 95 decibels. The device has a mute system that may be used to silence the beacon until takeoff, or until deployment of the parachute. In the silenced mode, the beacon will run for a week on a fresh battery, which means that you need not be concerned about how long the rocket sits on the launch pad. When beeping, the battery life is in excess of 24 hours, so you'll have plenty of time to look for a lost rocket or payload.
The SB20 measures 22.5mm wide by 15.75mm thick by 67.5mm long. Its weight with battery installed is only 18g, and it fits inside a tube with a minimum ID of 25.25mm. It will operate mounted in any orientation. This device runs on a 12-volt alkaline lighter battery, and it can be heard from a distance of over 30.5 metres.