This device a thing that you can set on the seat belt.
Why do we need it ?
Are your seats really clean?
Is the seat which you are sitting clean ?
Most of the people give the answer is "Yes".
In fact, there is a lot of bacterial made by your sitting there .
And the bacterial made your car and your wearing smelly.
What's the worse is your Child or Pet might lick it ,and they will get sick.
A level of quality or attainment