Ultrasonic Car Alarms
Ultrasonic car alarms are similar to microwave alarms, offering that second, higher and more advanced level of protection over a basic or easy-fit car alarm. However, an ultrasonic car alarm uses sound waves rather than an electromagnetic field to detect if anyone is gaining entry to your car.
Ultrasonic alarms are best used for monitoring the main cabin of a vehicle; and you'll often find these alarms installed by the manufacturers of modern cars. As these alarms are fully upgradeable you can even build a combined alarm with ultrasonic and microwave protection if you wish.