Heard across a street. Highly intelligent. A bike alarm like no other! $210 CAD. Direct from manufacturer: $120 CAD.
A June 2017 test. It seems to be a surface transducer being tested on a tin can–in this case, a Nellie’s laundry detergent’s–to check for improved loudness. IIRC all such tests failed to impress me. And they were indoors!
Surface Transducer, Loudness and a Tin Can
