Adaptil collar review

2 weeks ago I decided to buy Adaptil collar for Ardas as he can act stressed if he hear church bells, fireworks or similar noises. I didn't expect much as he is almost 7years old and fear might became a habit to him. For example, running to a dark quiet place for a few minutes and then come back as if nothing happened. So i did buy it. To be honest the only thing that I don't  like about this collar is that it only works for 4 weeks. I've noticed that Ardas became calmer during loud noise, so I believe it works.