Smaller and Compact – Ideal for discreet deployment Improved Design – Manufactured in Diecast zinc alloy and steel to prevent vandalism More Features – Can be activated by Timer, PIR, Remote Control and CCTV More practical – Has facility to automatically shut off after 20 minutes Internal/External Use – Also suitable for Accommodation Blocks, etc ...or so says the advert. But what actually is this - and how does it work? It's a well-known fact that children hear better than adults. More specifically, the younger we are, the higher sound (or frequency) we can hear. I noticed this very clearly the other week when Louise was here. I was charging my drill's battery and she ran in and asked me what the awful squealing noise was. I took the battery from its charger and she reported that the noise stopped. I was unable to continue charging the battery as the noise caused Louise some considerable distress. I could just about detect that there was a slight noise, Liz could hear nothing. So, it is this principle that the manufacturers or the Mosquito are seizing upon. Their exciting unit is mounted on the fronts of shops and by nervous residents in high-crime areas. When deployed, the unit emits a very high pitched noise which only the younger people can hear. The result is that teenagers are "considerably distressed" by the awful squealing noise, cease their loitering (either with or without intent) and go and loiter elsewhere. In our wildest dreams, perhaps they feel challenged about their negative lifestyles and seek to lead a more education-conscious and generous life. I'd buy one today if the effect could be narrowed down to teenagers intent on naughtiness. I know that is probably most of them, but I would feel sorry for the tiny minority who wish me only peace and joy. I would also spare a thought for younger children - or even babies who might be passing. Not much fun for them. So, until they learn to totally fine-tune the action of the Mosquito MkII, and with some considerable regret - I'm afraid I'll have to give it a miss. If, unlike me, you simply want to breathe as much destruction as you legally can on the younger members of our society, you may need to buy one quickly, as a governmental investigation is already underway. It is likely, one may reasonably assume, that this device will be outlawed in the near future.