Is home burglar alarm really useful?
Ordinary alarm mainly through the infrared, Menci detection whether there is an invasion. These technologies are quite mature and stable, the alarm response is quite fast. I used a different system for many years, in general, you can doubt her appearance vulgar, you do not doubt her mind beauty, she useful!
But you do not doubt its function. Although it is also very cheap, less than a hundred can buy a set of ordinary.
Home burglar alarm is of course useful. Some products look like work is very rough, like a toy.
